Alumni of the Ph.D. Program
The Richard Gilder Graduate School has produced 47 Ph.D. graduates since the first cohort matriculated in 2008.
2024 Graduates
Eva researched the anatomical and physiological changes that occurred in early fossil stem mammals and the ensuing development of unique structures found in the living mammal groups—monotremes, marsupials, and placentals. Hoffman combined anatomical study of key fossils from the past 150 million years with embryological, anatomical, and genetic data from modern mammals and other more distant vertebrate relatives, including preserved specimens in the Museum's and other scientific collections, to determine the evolution of defining features of mammals such as specialized tails, reproductive strategies, and olfactory systems—key traits that are crucial for reconstructing the evolutionary history of mammals. Originally from Maryland and South Carolina, Eva holds an M.S. degree in geological sciences from the University of Texas at Austin and a B.A. degree in anthropology from Yale.
Ernesto investigated the ways in which different parts of an organism are organized and are distinct from or interact with each other––the “modularity”––of approximately 460 million year old (Ordovician) trilobites. By employing 3D visualizations with a focus on the trilobite head, Vargas-Parra was able to examine and quantify shape variation to determine the drivers and patterns of modularity at 3 levels: static modularity within species at a single ontogenetic stage; modularity through ontogeny; and evolutionary modularity above the species level. Examination of patterns at these levels of modularity provide insights into how developmental processes, individual growth stages, and evolutionary pressures have shaped the function of trilobite anatomy over time. Ernesto earned his Master’s degree in geological sciences from the University of California, Riverside, and a B.A. degree in geophysical sciences from the University of Chicago. He is currently a Chancellor’s Postdoctoral Fellow at the University of California, Riverside.
Leroy investigates the macroevolutionary patterns of a group of North American snakes known as the Thamnophiini tribe, which includes gartersnakes, watersnakes, brownsnakes, and swampsnakes. By integrating diverse datasets from biogeography, morphology, ecology, and genomics within a comparative phylogenetic framework, Núñez explored how these snakes have diversified, particularly across a major biological barrier for this snake group and other organisms—the Western Continental Divide in North America. His research presents Thamnophiini as a prime model for understanding how adaptations occur in continental systems, expanding on understanding of diversification in other systems like on isolated islands. Leroy earned an M.S. degree in integrative ecology and a B.S. degree in biology, both from the University of Florida, and an Associate of Arts degree in zoology from Sante Fe College.
2023 Graduates
Herhold applied new genomic and imaging methods in the study of the respiratory systems of insects and related arthropods. Using the Museum’s advanced imaging facilities, including high-resolution x-ray micro-CT scanning, to generate holistic pictures of the entire respiratory systems of 13 insect orders, he produced a landmark three-dimensional visual atlas of insect respiratory systems. His comparative genetic analyses and detailed visualizations enhance the understanding of the relationships between insect respiration and movement, including the origins and evolution of flight, establishing an invaluable platform for future research. Herhold, who has a degree and industry experience in computer science, was a volunteer in the Division of Invertebrate Zoology at the Museum before beginning his Ph.D. at the Richard Gilder Graduate School.
Liyandja researched the evolutionary ecology and diversity of central African fishes in the carp genus Labeo, a major regional economic food resource. He explored Labeo distributions across different regions of the Congo River, the third largest river in the world, to better understand the mechanisms contributing to diversity, population, and genetic interchange across the genus, with significant applications for sustainable fishery management, finding that the Congo and Nile-Sudan river systems and Ice Age climate changes played central roles in the evolutionary radiation of carp species throughout Africa. Liyandja will continue his research through a postdoctoral appointment and Presidential Fellowship at the University of Toronto, in collaboration with the Royal Ontario Museum.
In her studies of the evolutionary history of milkweed longhorn beetles (genus Tetraopes), Gutiérrez Trejo focused on their molecular ecology and relationship to the usually-toxic host plants they feed on. By integrating the natural history, molecular ecology, and interactions of Tetraopes and their affiliated hosts, she generated the most robust evolutionary history ever for this group, helping scientists better understand the origins of these beetles and their co-evolutionary interactions with their host plants. Her longstanding interest in the diversity of beetles across different ecosystems has taken her on scientific expeditions around the world for extensive fieldwork, and she has described a variety of new insect species from her expeditionary and museum collection research.
Walling investigated the unique modes of metabolism in bacteria with a specific focus on the evolution of phototrophy—the ability to capture and use sunlight for energy. By sequencing, assembling, and annotating the entire genomes of two bacteria in the group Erythrobacteraceae, Alexandra generated the first comprehensive species phylogeny using genomic data for a total of 91 members of the Erythrobacteraceae family. Her research revealed multiple cases of the exchange of phototrophy genes and other genetic material across distantly related forms via horizontal gene transfer. Walling is currently pursuing her postdoctoral research at the University of Rhode Island.
2022 Graduates
James Gaspare Napoli studied uncertainty and the understanding of variation in the dinosaur fossil record. Non-avian dinosaurs dominated land ecosystems for more than 160 million years, achieving an extraordinary diversity of species, ecologies, and shapes, and sizes. Interpretation of dinosaur fossils is deceptively difficult, though, due to their rarity and variation within and across species. In addition to naming and describing new dinosaur species in detail, Napoli developed a novel approach to address these points of uncertainty, offering a different avenue for interpreting variation among fossil specimens and yielding exciting insights into dinosaur evolution.
Johannes Sebastian Neumann examined Placozoa—among the simplest animals on Earth—reconstructing their relationships to each other and to other animal groups, providing the first complete classification for any multicellular animal phylum, and investigating their genetic and reproductive responses to stresses of starvation or injury. For his research, Neumann collected specimens through fieldwork in aquatic and coastal environments on five continents.
Richard Benjamin Sulser focused his studies on the evolution of the mammal sensory system and how it responds to ecological transitions. Among living mammals, the enigmatic family of hedgehog-like African mammals known as tenrecs contains an exceptional range of sensory specializations. His research examined the neuroanatomy and genomics underpinning this disparity using a holistic approach.
Maggs X focused on understanding how changes to the genome influence complex traits in vertebrates, working to determine how genomic changes over evolutionary time influence reproductive modes in pit vipers. Although reptiles are widely known as egg-layers, many have live birth. Maggs X’s research employed whole-genome sequencing, gene family analyses, and modern statistical models to determine how suites of genes that are associated with female reproductive modes evolved across the snake phylogeny.
2021 Graduates
Alexandra Buczek focused her studies on the response of Southern Californian coastal marine mollusk communities to climate change approximately 3 million years ago, during which the Earth experienced a major warming analogous to modern climate change. Using only samples that she collected in the field, Buczek investigated whether precise numerical ages could be assigned to the geological units, compared the utility of two alternative paleo-temperature reconstruction methods, and determined the environmental factors that drove the spatial distribution of marine mollusks across three marine basins during this interval of substantial climate change, providing insights into potential responses of modern ecosystems to future climate warming. Buczek also engaged a diverse group of urban high school students in the Museum’s Lang Science Program.
Melissa Ingala examined how symbiotic gut microbes—the microbiome—facilitated the ecological radiation of New World bats, particularly with respect to their diets. Using samples she collected on three expeditions to Belize, she uncovered evidence that bats may rely on their gut bacteria to fulfill critical nutritional gaps in their diets. Exemplifying the unique fieldwork opportunities of the Museum’s Ph.D. program, Ingala also organized and led a collaborative expedition to the Tahuayo River near Iquitos, Perú to survey a diverse community of Amazonian bats.
Lukas Musher researched how avian biodiversity arose and accumulated in the Neotropics, combining phylogenomics, biogeography, population genetics, and statistical modeling to better understand the origins and assembly of bird communities. His research included field work to the Southwestern United States as well as to the Amazon—the most diverse terrestrial ecosystem and biome on the planet—where he collected many new specimens and documented bird diversity along the Roosevelt River in Brazil.
Kaiya Provost studied population genomics of North American warm desert birds, incorporating a wide variety of techniques in her research, including genomics, geometric morphometrics, bioinformatics, and bioacoustics, in addition to conducting behavioral surveys and specimen collection during field work throughout Arizona, Texas, and New Mexico. Provost also honed her skills as an educator as the Scientist in Residence for 5th grade girls at the Spence School.
2019 Graduates
You could say Jeremy Frank was born to study at the American Museum of Natural History. It was the very first public place he ever visited, with his twin brother, at one month old.
“It was a favorite place of my mother’s,” says Frank. “Guess she thought we would absorb it by osmosis—clearly, it worked!"
Fast forward to high school in Scarsdale, New York, where Frank took part in a school science research program through which he contacted and worked with Gilder Graduate School professor and Peter J. Solomon Family Curator James M. Carpenter, chair of the Museum’s Division of Invertebrate Zoology, on the taxonomy of vespine wasp (hornets and yellowjackets) species from China. A random assignment to study “bugs” in middle school during the local Science Olympiad competition had kicked off a consuming interest in insects, says Frank.
After earning a bachelor’s degree in biology at Case Western Reserve University, where Frank studied the flight of tobacco hornworm moths, he was back at the Museum working toward a doctorate in comparative biology, with Carpenter as his principal advisor. His research focused on the morphological, behavioral, and molecular phylogenetics of the solitary sand wasp genus Bembix, and developing the first preliminary evolutionary tree of life for these wasps that, like solitary bees, nest individually rather than in colonies.
“It’s been said they are one of the best-known stinging wasps but no one had ever studied their evolution,” says Frank. “There’s lots of basic information but a research synthesis gap.” In fact, Frank is proposing that this group now provides one of the best “model systems” in biology for studying the evolution of animal behavior.
“When Jeremy came back to the Museum for graduate work, he chose for his research a group that like the hornets we worked together on 10 years ago is large, charismatic, and well-known, the sand wasps,” says Carpenter. “But for such an obvious denizen of sandy areas around the world, there was a lack of phylogenetic investigation. Jeremy has certainly filled that gap.”
Confessing to a fondness for explaining things, Frank hopes to teach as well as continue his scientific research. While in college, he was co-designer and co-supervisor of the entomology test for the Northeast Ohio Regional Science Olympiad competition. Over the past four years, he served as a teaching assistant for the systematics course of the Museum’s long-standing and influential Research Experiences for Undergraduates program and an evolution class at the Richard Gilder Graduate School.
Frank also undertook fieldwork at the Archbold Biological Research Station in Venus, Florida, and at Museum’s Southwestern Research Station in Portal, Arizona, where he learned how to excavate ground nests with solitary bee expert Jerome G. Rozen, Gilder Graduate School professor emeritus and curator emeritus in the Division of Invertebrate Zoology.
During his time at the Gilder Graduate School, Frank says, he especially appreciated the scale of the Museum’s Research Library and access to the Museum’s vast collections, which he credits with actually helping him narrow his choice of research subject. A book had aroused his curiosity about Bembix and since the insect collections held nearly one-quarter of all the species in the world, he went to see what they looked like—and was hooked.
“My single favorite day as a scientist was getting to do that,” he says. “It was incredible!”
As a college student, Anna Ragni circled every course that interested her to settle on a major, with subjects like “Buried Cities and Lost Tribes” tilting her toward anthropology. But after taking a biology course in her junior year, she discovered she had a passion for figuring out how humans came to move the way we do.
So Ragni changed her focus to human origins—and never looked back. She earned a master’s degree in anthropology from the University of Arkansas in Fayetteville, where she researched teeth and the paleodiet of early hominins, spent a year as an assistant to the education and outreach coordinator in the Human Origins Program at the Smithsonian Institution’s National Museum of Natural History in Washington, D.C., and then began her doctoral studies in the comparative biology program at the Museum’s Richard Gilder Graduate School.
Over the last four years, she has studied with John Flynn, dean of the Richard Gilder Graduate School and Frick Curator in the Museum’s Division of Paleontology, and William E.H. Harcourt-Smith, Museum research associate, Richard Gilder Graduate School adjunct professor, and associate professor of anthropology at Lehman College (CUNY), to study fossil hominin paleobiology. Her focus: understanding how primate bones change through life, particularly in light of locomotor differences, using high-resolution micro CT scans to examine the honeycombed internal bone structure of many individuals from several modern primate species and exploring what they might tell us about the evolution of bipedalism in fossil and modern humans.
“Anna’s Ph.D. research developed a fascinating new approach for determining how changes in locomotion, as primates grow from young to old or between different species, affect the detailed structures inside their hand and foot bones. From this work, she’s already begun revealing exciting new insights into how our fossil relatives moved and how our own species evolved such a distinctive style of locomotion—walking upright,” says Flynn.
Ragni also honed her skills as an educator, engaging students in the Museum’s Youth Initiatives and Adventures in Science programs with her research results, as well as presenting her science to undergraduate biology students, the New York Lady Science Forum, and high school students for whom she co-created and co-taught a course about how scientists use state of the art visualization methods to understand the evolution of human bipedalism by studying living and fossil primates. At the same time, Anna mentored women studying at Columbia and Tufts, and a high school student headed for Stanford.
Ragni found the Richard Gilder Graduate School much more multidisciplinary than programs in institutions where various disciplines function in separate enclaves. “I didn’t come from a biology background, and I’ve learned so much here from faculty and fellow students,” she says.
A strange thing happened to Kelly Speer on her way to a career as a high school English teacher. She was recruited to prepare a specimen for a natural history collection.
“I loved it!” she says, of that unexpected gig in the mammalogy collection at the Museum of Southwestern Biology, where scientists study a diversity of mammals, including the endangered Mexican gray wolf, with a view to understanding biodiversity and evolution. She was captivated by seeing this top predator up close. “You get to experience wildlife and biodiversity in a way you never would otherwise,” she says of working in museum collections.
It all started when, as a first-year undergraduate at the University of New Mexico, Joe Cook, a curator of mammalogy at the Museum of Southwestern Biology, asked her if she might be interested in volunteering in the collection. Speer, who had planned to major in English literature, signed on for a year, then she began working with two graduate students, gaining deeper experience with molecular genetics research and parasitology.
That work led to a master’s program in biology at the University of Florida, where Speer began studying bats and bat flies, the subject of a paper for which she was lead author, published in July 2019, assessing buffy flower bat populations across the Bahamas through genetic material derived not from the bats themselves but instead from their blood-feeding parasitic bat flies!
Her research as a doctoral student at the Richard Gilder Graduate School built on her prior analyses to focus on the bacterial microbiome found in bat flies; this ecosystem of bacteria living in the flies impacts the ability of the fly to feed on blood and transmit disease to its host bat. Taking advantage of the grad school’s fostering of interdisciplinary research, she was advised by Gilder Graduate School Professors and Museum Curators Nancy Simmons in the Department of Mammalogy, Division of Vertebrate Zoology, and Susan Perkins in the Division of Invertebrate Zoology. Using samples that she collected herself in the field in Mexico and Belize, along with other previously collected samples from Brazil, Speer investigated patterns of variation in bat fly microbiomes and how this variation may affect the ability of parasites to transmit disease-causing pathogens among bats.
“Kelly’s work is highly innovative,” says Simmons, “and fills an important gap in our understanding of microbial diversity in parasites, like bat flies, that can move across different host individuals and species, and how this diversity may affect disease transmission among bats in complex tropical communities.”
Speer says she especially appreciated having advisors who could offer insight into professional advancement for women in science, giving her confidence to forge her own path ahead. She also found herself awed by scientists and explorers from the Museum’s past.
“I hadn’t expected the incredible gravity I would feel by seeing a bat collection that had been curated by [longtime Museum Curator] Karl Koopman or seeing dioramas prepared by Carl Akeley,” she says, naming an internationally recognized expert on bats and the legendary explorer who developed habitat dioramas.
Speer began postdoctoral research at the Smithsonian in January 2020, with support from two prestigious and competitive fellowships.
2018 Graduates
Allison Bronson can tell you the exact moment she chose her career path: she was 8 years old, standing in a salt marsh on a trip with her grandmother. She recalls, “A ray swam by my foot, and I thought, 'This is it! I’m going to be a shark scientist!'”
Fast forward 20 years and Bronson has done just that, using cutting-edge techniques to study evolutionary relationships among ancient sharks and even identify a fossil once thought to be a plant as, more likely, a 70–85-million-year-old cartilaginous fish. Her innovative analyses using 3D reconstructions from high-resolution micro-CT scanning in the Museum’s Microscopy and Imaging Facility enabled her to visualize the cranial anatomy of living and fossil fishes, and reconstruct how ancient sharks moved their jaws when feeding.
Now teaching Introductory Zoology and an Ichthyology lab, and pursuing research at her undergraduate alma mater, Humboldt State University in northern California, Bronson first came to the Museum in 2013 as part of the Museum’s National Science Foundation-funded Research Experience for Undergraduates program. At the time, she worked with paleontologist John Maisey, now curator emeritus, who subsequently would become her doctoral advisor at the Richard Gilder Graduate School.
The Museum’s doctoral program in Comparative Biology was a natural next step for her. “I love to work with collections, particularly holotypes or really old specimens I’ve recognized from figures or papers—seeing them in person never got old for me,” she says. “I liked the social environment of the Museum—the nerd paradise that is the American Museum of Natural History—and I liked that you can complete a Ph.D. (degree) in four years flat.”
While a graduate student, Bronson also took advantage of unique opportunities for educational outreach, giving collections tours to students of all ages, explaining shark evolution for the Museum's science website for kids, OLogy, and answering questions about shark fossils for Museum audiences on Facebook Live. She was also one of the paleontologists featured in the "Six Extinctions in Six Minutes" episode of the Museum’s award-winning Shelf Life series, discussing the end-Devonian mass extinction about 360 million years ago and the giant placoderm Dunkleosteus that prowled the ancient oceans before the extinction event.
It isn’t every day you discover your career mentor in grade school. But that was the case for Daniel Barta, who has just finished four years studying dinosaur growth and development under the Museum’s Macauley Curator Mark Norell in the Division of Paleontology.
“We were reading in elementary school about the first feathered dinos found in China, and I read a related article about Mark’s work in the Gobi Desert about nesting dinos,” Barta recalls. “I remember thinking Mongolia would be a cool place to travel and that maybe when I am a professor, I‘d get to do that!”
After earning undergraduate and graduate degrees in Earth Sciences (specializing in Paleontology), Barta was accepted to the Richard Gilder Graduate School. Within a year he found himself accompanying Norell to the Gobi Desert on a joint expedition of the Museum and the Mongolian Academy of Sciences, long before becoming the professor he’d dreamed about as a child. Soon after that, Barta co-authored a paper about a specimen of the ornithischian dinosaur Haya griva found there.
What surprised Barta most about his time in the Museum’s Ph.D. program was how much he came to appreciate the old along with the new. “I realized in a tangible sense what a great history the Museum had, the personalities behind the artifacts, and that I was a part of that,” he says. Through the application of new analytical approaches, including CT scanning and ultra-thin bone histology studies, the research on historical specimens remains at the cutting edge of science. “The Museum’s collections are that link,” says Barta.
Working with Norell and with his co-advisor Jin Meng, curator of fossil mammals in the Division of Paleontology, Barta published numerous scientific papers, served as a scientific advisor for and a co-instructor for the Lang Science Program high school course about the Museum’s traveling exhibition Dinosaurs Among Us, participated in an international press conference announcing the formal scientific name of the Museum’s recently-mounted titanosaur exhibit, and engaged with the Museum’s social media followers on topics ranging from dinosaur growth on Facebook Live to why pterodactyls aren’t dinosaurs.
Barta embarked on his professorial career as a lecturer teaching human anatomy and introductory biology at California State University, Los Angeles, before moved becoming an assistant professor of anatomy and cell biology at Oklahoma State University.
A serendipitous trip as a child to the Smithsonian National Museum of Natural History in Washington, D.C., set Anna Holden on a path to a career in Quaternary entomology, the study of insects from about 2.6 million years ago to the present.
Armed with a combined B.A. degree in biology and studio arts and a master’s degree in museum studies, Holden worked at numerous museums before arriving at the Museum’s Richard Gilder Graduate School as a Ph.D. student in 2014. “Not only did the Gilder School have the facilities, material resources, and curators—just beyond extensive support—the program allowed me to develop my own path,” says Holden.
As a doctoral candidate at the Museum, she conducted research on fossil and modern beetles at Rancho La Brea Tar Pits—one of the world’s richest Late Pleistocene-to-Holocene fossil sites—that revealed that the climate and ecosystem of pre-historic Los Angeles likely was very similar to modern environments today. Among her results: the finding, based on generating high-precision radiocarbon dates and analyzing an extensive amount of fossil insects from the tar deposits, that southern California’s climate has been relatively stable for at least 50,000 years except during the Last Glacial Maximum approximately 26,000 to 19,000 years ago.
In graduate school, Holden’s advisor and co-advisor were Peter J. Solomon Family Curator James Carpenter and Curator Ross MacPhee in the Division of Vertebrate Zoology, and she was closely mentored on her insect faunal work by Quaternary entomologist Dr. Scott Elias from Royal Holloway, London.
After completing her Ph.D., Holden worked as a project manager for the African Natural History Research Trust, where she applied her skills as a Quaternary research scientist to target the best places to study African insect biodiversity and conserve critical habitats that are rapidly disappearing. “Science is a team sport,” Holden says. “I just love the collaborative nature of what I do.”
“I have always been a naturalist at heart,” says Spencer Galen, who, after completing his graduate studies at the Museum, headed to the Academy of Natural Sciences of Drexel University in Philadelphia to begin as a National Science Foundation postdoctoral fellow. “As a kid, I learned the names of all of the birds, butterflies, and dragonflies that lived in the forest behind my house. But birds were always my primary interest.”
The focus of Galen’s master’s degree was the study of parasites infecting birds. So, when he decided to continue this research for his doctorate, he chose the Richard Gilder Graduate School specifically to work with Susan Perkins, curator in the Division of Invertebrate Zoology and a leading expert in the evolutionary relationships of malaria parasites.
Working with Perkins as his principal advisor, Galen led a research analysis recently published as the most comprehensive Tree of Life to date for malaria parasites, generating some of the first genetic data for malaria species from poorly studied evolutionary lineages—such as those infecting deer, turtles, bats, and numerous species of birds—that were missing from previous analyses.
In 2015, Galen participated in a joint expedition by the Museum and the Cuban National Museum of Natural History to Cuba's Alejandro de Humboldt National Park.
“I got to meet so many incredible Cuban scientists,” says Galen. “I feel that trip really open the opened the floodgates for sharing ideas, and I was excited to be a part of the beginning of a new era of collaboration.”
In 2016, he organized a trip with Paul Sweet, the Museum’s collections manager for the Department of Ornithology, to central Alaska, an expedition that led to a paper integrating ecological and genetic data to identify species within the avian malaria parasite genus Leucocytozoon. But the field work also gave Galen a chance to savor other aspects of his childhood love: the outdoors.
“We drove the historic Denali Highway, a barren stretch of dirt road that cuts through the middle of Alaska that truly feels wild,” he says. “We spent those summer weeks watching moose, watching out for fresh grizzly bear tracks, and wondering when the sun would ever set. It never did!”
Growing up, Adolfo Lara thought he wanted to become a physician or work for NASA, two careers he saw on popular television shows. But when he entered college—the first in his family to do so—he discovered another path after a friend asked him to help out in a microbiology lab.
“I wasn’t aware there was this whole other world of being a scientist for people to pursue,” he says. “There was no TV show for that!”
This was the beginning of his journey into the field of evolutionary biology. As an undergraduate, Lara used DNA markers and entire genomes to study a plant pathogen that kills grape plants, a problem for the wine industry. As an intern at a health center, he studied retinal neurons and also mast cells in search of therapeutic allergy drugs for people with respiratory diseases. And while still a student at the University of Houston-Downtown, Adolfo participated in the Museum’s summer Research Experience for Undergraduates program, undertaking research with Associate Curator Estefanía Rodríguez in the Division of Invertebrate Zoology to help describe two new species of deep-sea anemones using well-established descriptive techniques and developing novel DNA markers unique to anemones.
In 2013, he entered the Richard Gilder Graduate School’s doctoral program—during which he was selected by the National Science Foundation for its prestigious Graduate Research Fellowship Program—with Rodríguez as his Ph.D.-degree advisor and Curator Rob DeSalle, also in the Division of Invertebrate Zoology, as his co-advisor. While working on his dissertation, Lara drew on his prior work in genomics, neurobiology, and evolution to ask and resolve innovative questions about the nervous systems of cnidarians, the group that includes sea anemones and jellyfish, with a view to use better reconstructions of the ancestral condition of neurological processing in animals to enhance understanding of complex brains like those in humans.
Taking advantage of the Richard Gilder Graduate School’s novel curriculum, Lara also took part in a variety of educational outreach efforts, from a speed-science event at which he showcased Museum research and collections to a Facebook Live broadcast. It is important, he says, to share your enthusiasm for your work and inspire the next generation of scientists: “As someone once said, ‘Passion makes everything contagious.’ And it makes it fun!”
For Rachel Welt, a funny thing happened on the way to medical school. She fell in love with iguanas—well, with environmental biology, which led her to develop a passion for iguanas.
“About halfway through college,” says Welt. “I realized that if ecology and biodiversity really interest me, I could apply the lab skills I had developed through medical research in a different way.”
She added an environmental biology minor to her pre-medical studies and went on to earn a master’s degree in ecology and systematics, at the same time earning an advanced certificate in conservation biology. For her master’s thesis, she studied the genetic response of populations of field mustard (Brassica rapa) to a climate change event. In 2012, hoping to shift her focus in the direction of biodiversity and conservation, she volunteered to work at the Museum with herpetologist Christopher Raxworthy in the Division of Vertebrate Zoology on his ongoing research on Madagascar and the origins of its unique biodiversity.
“DNA is DNA,” she says, explaining the transition from research on plant genetics to her work as a volunteer using gene sequencing to identify new cryptic species of Madagascar’s herpetofauna, different species that look virtually the same but have diverged in other ways.
“There is a lot to be discovered when you look beyond the morphology of these frogs, geckos, iguanas, and chameleons. With this work, we used DNA sequences to barcode these cryptic species.”
By the time she entered the Richard Gilder Graduate School in 2014 with Raxworthy as her principal advisor, she had narrowed her focus—and fascination—to one family of iguanas (Opluridae) whose isolated presence on Madagascar has long been a biogeographic mystery. In 2016, after years of working only with DNA samples in the lab, she traveled to Madagascar to meet her subjects first hand—field work she discussed on Facebook Live.
“It was amazing,” she says, “It was so important to finally have the chance to put everything into context and understand Madagascar’s landscape, and to actually see many of these unique animals for the first time.”
For her Ph.D. dissertation, she investigated the evolutionary history of Madagascar’s iguanas, the events driving their diversification, and their conservation status. Back in the lab, she completed extensive genetic studies that suggested as many as eight previously unrecognized species, double their previously known diversity. Since finishing her doctoral studies, Welt has stayed on at the Museum to confirm, fully describe, and formally name these new species.
“These iguanas are very special—they are found nowhere else on Earth,” she says. “My ultimate goal is to understand the threats to their survival and their vulnerability to environmental factors from climate change to rapid habitat loss.”
2017 Graduates
The first time Zac Calamari stepped foot in the Museum was as a dinosaur-obsessed 11-year-old.
He took one look around and said, “This is where I want to work!”
Fast forward to 2013, when he began four years at the Museum’s Richard Gilder Graduate School working toward his Ph.D. degree in Comparative Biology.
His journey was not without twists and turns. Calamari, now 28, dropped dinos and, as an undergraduate at the University of Michigan, initially majored in history with a focus on medieval Japan. But while on a geology field trip to the Rocky Mountains, he couldn’t help but marvel at the age of the specimens—and decided to return to science. “I was up in the mountains breaking open rocks,” he said, “And realized history is a few thousand years old but these rocks were hundreds of millions of years old!”
After graduating with a double major in Geological Sciences and History, he stayed on in Ann Arbor to study mammoth tusks and participate in research on the comparative morphology of two remarkably preserved baby mammoth mummies, Lyuba and Khroma.
He entered the Museum’s doctoral program in 2013, where he concentrated on shape development and gene expression of skull appendages—or “head gear,” as he likes to call it—of even-toed hoofed mammals such as moose, pronghorns, cattle, antelopes, deer, and giraffes.
Besides fulfilling his boyhood dream, coming to the Museum offered Calamari a chance to work with his mentor, John Flynn, who is dean of the Richard Gilder Graduate School and Frick Curator of Fossil Mammals in the Division of Paleontology. Calamari was also drawn by the Museum’s massive collections, world-class natural history library, and dedication to public outreach.
“Here, public outreach is built into what we do,” says Calamari. “Sharing what we know is the point.”
Over the course of his four years, Calamari has done his share, explaining his work to students from the John Hopkins Center for Talented Youth, children in the Museum’s Discovery Room, and on live segments for the Museum’s Facebook where, he says, “In 15 minutes, 20,000 people heard me talk about horns and antlers!”
In mid-October, Calamari starts postdoctoral work in Ophir Klein’s biomedical lab at the University of California, San Francisco, shifting his research focus to different head hardware—gnawing rodent teeth that grow forever—in the hope of understanding the evolution of this trait and identifying medical applications for humans.
“Plants are so much weirder than animals!” says Dr. Paasch, 30, who will be receiving her Ph.D. degree in Comparative Biology from the Museum’s Richard Gilder Graduate School (RGGS) on September 27. “I didn’t realize how interesting they were, how diverse.”
Through college and while earning her Master’s degree at Cal State L.A., she studied the abundant unique plant life of Southern California, including Syntrichia caninervis, a moss in the Mojave Desert that can survive without water for 100 years. At the Museum, Paasch worked with Associate Curator and Associate Professor Eunsoo Kim to research microscopic green algae that eat bacteria instead of relying only on photosynthesis, to find out what we can learn from them about the evolution of chloroplasts.
Aside from academics and research, Paasch also helped with public outreach. She contributed details about the desert moss to the Museum’s Life at the Limits exhibition and set up a microscopy booth for elementary schoolchildren at the annual Family Party. She also served as a mentor for college students in the longstanding Research Experience for Undergraduates program at the Museum. And she took a leading role in getting the Museum actively involved in the annual Society for Advancement of Chicanos and Native Americans in Science conference, which advises and supports minority students applying to graduate school.
“It is necessary to broaden participation of underrepresented groups in science, and I am working to help remove barriers to academia for ethnic and racial minorities, and women,” says Paasch.
With a four-year research and mentorship fellowship from the National Institutes of Health, Paasch will return next month to California to start post-doctoral research in Katie Pollard’s bioinformatics lab in the Gladstone Institutes at the University of California, San Francisco. There, one of the central lessons of her time at the Gilder Graduate school should stand her in good stead. Paasch says Dr. Kim has always encouraged her to avoid being pinned down to a single species, and instead to approach analyses of traits and relationships through a wider lens.
Says Paasch, “Rather than the organism being studied, what’s important are the questions we are asking.”
As a boy growing up in Cranbury, New Jersey, Michael Tessler relished weekend excursions with his family to the lush Longwood Gardens in Kennett Square, Pennsylvania, the Academy of Natural Sciences in Philadelphia (today part of Drexel University), and the American Museum of Natural History—where, to this day, he finds the dioramas thrilling. “That doesn’t go away,” he says.
He also fondly recalls trips to an aunt’s home in the Catskills where he would delight in jumping off the deck into a lake full of tadpoles and turtles. Tessler turned his curiosity into a B.S. degree in natural history from Sterling College in Craftsbury Common, Vermont, and a Master’s degree in biology from Fordham University, where he studied the ecology of mosses.
“I still want to know about everything I see in the woods, and under the rocks I turn over in the river,” says Tessler.
Which brings us to leeches. Intrigued by a book he’d read about blood feeders and his own first-hand experience of terrestrial leeches during a trip to Tasmania in 2012, he jumped at the chance to work with Mark Siddall, curator in the Museum’s Division of Invertebrate Zoology and a renowned parasitologist. When Tessler matriculated at the Richard Gilder Graduate School in 2013, Dr. Siddall became his advisor.
In 2015, Tessler accompanied Siddall on a Constantine S. Niarchos Expedition to Cambodia, where they searched for leeches whose gut contents could help determine which rarely observed mammals were being fed upon by the leeches, documenting their presence in a particular area. (Watch the video below on more about the expedition and on how leeches can provide scientists with clues crucial to conservation.)
The following year, Tessler, Siddall and other museum colleagues described a new species, Chtonobdella tanae (named in honor of the novelist Amy Tan)—the first-ever description of an extant soft-bodied species to use the technology of computed tomography (CT) scanning.
Tessler’s time at Gilder was also marked by working with students at all levels, including college biologists through the Museum’s NSF-funded Research Experience for Undergraduates, high school students through the Science Research Mentoring Program, and even third graders in the Museum’s Science and Nature program. “I got to talk to the kids who were like me when I was growing up,” he says.
This month, Tessler began working as a postdoctoral fellow with the NYC plant genomics consortium through NYU and the Museum. This research—on the evolutionary biology of flowering plants—brings him back to botany, an area he concentrated on while earning his Master’s degree. But he hasn’t abandoned leeches, either, and there are several projects with Siddall yet to be published.
“You learn a lot by switching around,” says Tessler. “Animals do things plants don’t do. Leeches do things dinosaurs don’t do. You get a pretty good picture of biodiversity when looking at a lot of organisms, which is what I’m interested in.”
2016 Graduates
When Jonathan Foox was an undergraduate at George Washington University (GWU) studying cell biology, he wasn’t quite sure where his studies would take him. Would he go to medical school? Or perhaps pursue research science?
But after he spent a summer studying the diversity of microbial life at Rehoboth Beach, Delaware, through a National Science Foundation–sponsored “REU” (Research Experience for Undergraduates) internship at GWU, he realized how interested he was in spending time in the field and analyzing the evolutionary relationships among poorly-understood groups of living things, a field of biological research called phylogenetics.
And so Foox, who originally hailed from just outside New York City, made his way to Manhattan’s Richard Gilder Graduate School (RGGS), where he helped determine the first genome of bedbugs, and studied sea anemones and a related group of tiny living things you’ve probably never heard of: myxozoans.
As Foox describes them on his website: “[t]hese bizarre, microscopic parasites are the world's smallest animals, and can be found inside of economically critical fish (among other hosts) around the world.” While some stages of their life cycle can be visible to the naked eye, others can be as small as one-tenth the size of a single grain of sand, Foox says.
Most myxozoans are parasites of aquatic animals, so to collect them for his research studies, Foox conducted fieldwork in watery places, including expeditions to California, the Gulf Coast of Mississippi, and Bermuda.
Working with RGGS Professor and Curator Mark Siddall, Foox set about trying to understand where myxozoans fit into the tree of life. Since the mid-19th century, it had been believed that they were protists—mostly single-celled organisms that are neither plant, animal, nor fungi, but that they do have DNA within their nuclei, distinguishing them from bacteria and other organisms with simpler cells. However, recent research has confirmed that they are more closely related to cnidarians, a group that includes jellyfish, corals, and sea anemones. That means these tiny animals have structural similarities with animals that are to them as large as Mount Everest is to a human.
But while those animals aren’t parasitic, myxozoans are. Foox’s research at RGGS helped establish how this strange evolution evolutionary turn might have taken place.
Foox spent some of his time at the Museum devising novel computer programs to help him, and other scientists, analyze complex data. One problem encountered by those who study myxozoans is that when you collect their DNA you also often collect the DNA of the host fish or other animals, thereby contaminating the samples. So Foox devised a quicker, computer-based “bioinformatics” method for weeding out the extra non-myxozoan DNA.
“I dabbled in computer programming as a kid,” Foox says, but at the Museum he basically taught himself to code what he needed to analyze his own research data.
Now, Foox is moving across town to the Weill Cornell Medical College, where he’ll continue to use computer science to elucidate the workings of life. In this case, he is joining the lab of Chris Mason at the Institute for Computational Biomedicine, to study, cell by cell, how cancer evolves—and, hopefully, help to determine how it might be stopped in its tracks.
Growing up in Queens, New York, Stephanie Loria was always interested in animals, particularly insects.
“I’d wanted to be an entomologist since I was 10 years old,” she says.
To make that dream come true, Loria gravitated to the American Museum of Natural History early on. By high school, she was spending afternoons in the Museum’s Science Research Mentoring Program (SRMP), where she assisted in the work of the Center for Biodiversity and Conservation (CBC).
In college at Sewanee in rural Tennessee, she studied cave-dwelling millipedes—many-legged arthropods related to, but distinct from, the insects she was fascinated by as a child. As her studies broadened, so did her invertebrate interests. Soon, it was arachnids, a group that includes spiders and scorpions, which were dominating her attention.
Following a research fellowship at Chicago’s Field Museum, Loria returned home to New York—and to the Museum. As a Ph.D. student in the Richard Gilder Graduate School, she focused on the study of scorpions alongside Curator Lorenzo Prendini, and received numerous awards including a U.S. National Science Foundation (NSF) three-year graduate research fellowship, a major NSF doctoral dissertation improvement grant, and an Explorers Club award for expeditionary work. In the course of her Ph.D. studies, she spent about four months in the field, mainly in Southeast Asia, collecting specimens to bring back to the Museum for additional study and permanent archiving.
“At a cave in Laos, we had to swim hundreds of meters through an underground river, in our caving gear,” Prendini recalls. “Within minutes of our arrival on land, Stephanie had found a blind, depigmented millipede and a pale, sightless scorpion—two of many new species she discovered in her travels!”
Analyzing morphology and DNA characteristics, Loria indeed described those and a number of other new species within the scorpion group Chaerilidae. Her doctoral dissertation also focused on novel analyses of the eye diversity among all scorpions; most species have one pair of dorsal eyes, along with up to seven additional pairs found along the animals’ sides.
During her Ph.D., Loria’s journey came full circle when she served as a mentor to a high school student in the SRMP program, the same place where she got her own start in science.
Soon, she heads to the California Academy of Sciences as a Postdoctoral Fellow, to continue studying scorpions, her early dreams of becoming an entomologist realized—more or less. Technically, she’s now a skilled arachnologist, studying eight legged-arthropods, rather than their six-legged insect relatives. Still, it’s closer than most folks get to their life plan at 10 year old. As Loria likes to say, “I was only off by two legs.”
Coming from a family of chemists, Lauren Oliver recalls being introduced to microscopes and chemistry sets at a young age. Those weren’t the scientific tools, though, that held her interest.
“I was interested in animals,” she says.
In the woods and streams near her childhood home in Alabama, Oliver would collect frogs, feeding them grass until she realized that probably wasn’t what they ate.
“And I would always let them go,” she makes sure to point out.
As a freshman at Louisiana State University, she found her way to the school’s Museum of Natural Science, where she studied in the lab of herpetologist Chris Austin. From there, she quickly entered the world of academic (and field) research, doing lab work and publishing three research papers as an undergraduate, including her senior thesis examining hidden species diversity in a wide-ranging frog species from New Guinea, Mantophryne lateralis.
While at the Richard Gilder Graduate School, she received a prestigious 3-year U.S. National Science Foundation graduate research fellowship, collaborated with Professor and Curator Chris Raxworthy, and traveled to New Guinea with support from a National Geographic Society “Young Explorers” grant for her to collect and observe frogs in the genus Papurana. The many species in this genus, similar to the North American leopard frog and bullfrog, range from a minuscule 30 millimeters long to as large as 160 millimeters, or just over six inches. The bigger example, known as the Arfak Mountains frog, is the largest frog species in New Guinea.
Wanting to get a comprehensive look at the Papurana, Oliver utilized other museums’ collections as well the Museum’s own extensive records. These include many specimens from the Museum’s pioneering 1930s expeditions to the interior of New Guinea, one of the world’s greatest biodiversity hotspots, sponsored by Museum supporter Richard Archbold. Information from Archbold’s expeditions not only added to Oliver’s research, but also helped guide her to sites she could revisit decades later to collect further frog specimens.
While analyzing her specimens’ morphology and genomic data – “I spent a lot of time at the Institute for Comparative Genomics,” she recalls – Oliver also served as an educator, advising students in the Museum’s Science Research and Mentorship Program and teaching laboratories for the Richard Gilder Graduate School’s core course on systematics.
After defending her dissertation, Oliver returned to the Gulf Coast, where she now is a biology instructor at Bishop State Community College, and she will soon publish new research on the remarkable diversity of Papurana frog species in New Guinea.
With some 1.8 million people, the city of Vitória on Brazil’s coast is no nature reserve. So when Bernardo Santos was growing up there, he channeled his love for animals into those that were “at hand”: insects. Santos’s father was a beekeeper, and Bernardo helped with the bees. He also had a butterfly board, where he’d collect and pin specimens representing the diverse species that he’d found flying through the hilly streets and avenues of Vitória.
Santos studied at Universidade Federal do Espírito Santo in his home town, earning both his Bachelor’s and Master’s degrees, and where he later worked as a university lecturer, teaching subjects ranging from cell biology to paleontology to undergraduate students before moving to New York to start his doctoral studies at the Museum’s Richard Gilder Graduate School (RGGS). His primary advisor was Peter J. Solomon Family Curator in the Division of Invertebrate Zoology and RGGS professor James Carpenter.
The wide world of so-called parasitoid wasps would become his domain while he worked toward his Ph.D. Unlike eusocial bees and ants, which are highly socially organized and live in colonies (as do some members of one family of wasps, the Vespidae), most wasp species live solitary lives, coming together only to mate. Parasitoid wasps, of which there are over 70,000 known species (more than all species of vertebrates), are far more common.
They are also, says Santos vividly, “like Ridley Scott’s Alien!”
Female parasitoid wasps lay eggs in the bodies of other insects or arachnids. There, the eggs grow and develop into larvae, which consume their unlucky hosts from the inside. Then, the larva pupates—that is, grows larger and spins a cocoon for itself, in which to continue to develop and grow before metamorphosing to emerge from the cocoon as an adult wasp.
While parasitoid behavior may seem unusual, Santos points out that it evolved much earlier than the sociality we associate with insects like bees and ants. Amazingly, a species of parasitoid wasp exists to prey upon nearly every other species of insect and of many of their arachnid relatives.
“These wasps are the single most effective insect-population control in nature,” says Santos.
Santos’s passion for describing previously unknown species of wasps drove his fieldwork and studies at the RGGS. He traveled far and wide, into field sites and museum collections alike, to identify new species. By examining collections around the world, he already has described almost a hundred new species of parasitoid wasps during his young career.
In describing one of these new species, Santos worked with public school 6th-graders in New York’s Washington Heights neighborhood to choose its new name. Together, they landed on the name “La luz brilliante” or “the brilliant light” which became part of its official scientific Latin name, Nesolinoceras laluzbrillante.
He was inspired to undertake this special type of outreach by his time at the Museum, where he also had the opportunity to mentor two high-school students in the AMNH’s Science Research Mentorship Program, who studied an Andean species of wasp. In his four years at RGGS, Santos also spent extensive time in the molecular lab, sequencing DNA for hundreds of species of parasitoid wasps.
Using those DNA data to unravel the evolutionary history of these wasps, and building an “evolutionary family tree”; measuring and photographing specimens, and then using statistical tools to quantify their similarity in shape. By combining shape data with evolutionary history, Santos was able to understand how different modes of parasitism (using different hosts, etc.) influenced the evolution of their body shapes.
Following commencement, Santos will continue his scientific research on parasitoid wasps as a Peter Buck Postdoctoral Researcher at the Smithsonian National Museum of Natural History, in Washington, D.C.
When Akinobu Watanabe was a young boy in Japan’s Fukushima Prefecture, his parents recorded a Discovery Channel–style documentary about the history of Earth.
“Back then you had VHS,” recalls Watanabe, “and I watched it so much that the tape kept getting damaged.”
But the story of the prehistory of the planet and evolution of life so riveted him that he would keep watching even as the tape begain to deteriorate. The documentary, after all, had much to say about the animals he was most interested in: dinosaurs.
After graduating from high school in Michigan, Watanabe studied in the lab of dinosaur paleontologist Paul Sereno at the University of Chicago, where he began to hone his passion and expertise in the subject. For his Master’s, he went to Florida State University to undertake research on modern alligators and crocodiles, close relatives of dinosaurs, allied together in a group called archosaurs (“ruling reptiles”).
There, he learned new research methods like sophisticated statistical analyses of bone shapes and studies of bone histology—slicing thin slivers of the fossilized bones to learn about the age and growth of animals they came from. In addition, he became skilled in computer programming, to deal more effectively with the vast volume of data his research produced, a skill that he would continue to practice alongside his Museum advisor, RGGS Professor and Macaulay Curator of Paleontology Mark Norell, while publishing more than a half-dozen scientific papers and several new computer programs.
At RGGS, Watanabe, who received a prestigious 3-year U.S. National Science Foundation graduate research fellowship and doctoral dissertation improvement grant, as well as grants from ExxonMobil Geosciences, Sigma Xi, the Society of Vertebrate Paleontology, and the Jurassic Foundation, found himself at the heart of dinosaur paleontology’s colorful past (and its vibrant present). He joined multiple Musuem expeditions to the famed fossil fields of Mongolia’s Gobi Desert, where Museum legend Roy Chapman Andrews had found the first nests of dinosaur eggs in the 1920s.
While in the Gobi, Watanabe, too, discovered a dinosaur-egg nest, as well as filming one of his field expeditions to Mongolia with Google Glass technology. He also collected pterosaur and mammal bones as well as dinosaur egg shells with Norell in Romania, where the team slept in hotels and ate fine European food, a very different sort of trip from the rugged days camping under the stars in the Gobi Desert.
Back in New York, Watanabe collaborated with a number of researchers from the Museum and partner institutions to study the evolution of specialized brains of modern birds from their dinosaur ancestors. To study the shape of dinosaur brains that do not get preserved directly as fossils, he used high-resolution x-ray CT scans of fossils to create 3-D reconstructions of the bony braincase that enclosed the brains. By comparing how this shape changes through development from embryo to adult, and evolutionary time, his research has shown that the origins of the unique developmental mechanisms required to assemble a “flight-ready” brain occurred in piecemeal fashion spanning non-flying dinosaurs to their modern bird relatives. He also built innovative computer programs to test existing methods that researchers use when creating evolutionary trees and collect data on the shape of bones.
Now, Watanabe has expanded his view to include more lifeforms. After defending his RGGS dissertation, Watanabe has moved to a leading research lab at University College London, in the U.K., supported by European Union grant fellowship, where he and his colleagues are working to elucidate the evolution of the skulls and brains of all tetrapods—the group that includes not only dinosaurs and birds, but also mammals, reptiles, and amphibians— seeking to better understand the evolutionary origins every animal with a backbone and four limbs, living and extinct.
2015 Graduates
Growing up in the Southwest, Phil Barden was always intrigued by animals, spending his free time “doing kid stuff,” like catching snakes and lizards. But in high school, when he mentioned his interest in nature to a guidance counselor, the man discouraged him. “Naturalists,” he said, “don’t exist anymore.” They were from “olden times,” an extinct species.
Despite this pessimistic counsel, Barden remained determined to find a way to study nature. In college at Arizona State University, he worked in a biology lab where the researchers studied eusociality, a trait of some animal groups, including insects like bees and ants, wherein most individuals forego reproduction for the benefit of the greater community. In many ant colonies, for example, there is just one queen; the workers are generally sterile females, while males emerge only briefly to mate with fertile virgin queens before dying soon after.
The more Barden learned about the lives of ants, the more fascinated he became. There are over 13,000 known species of these insects, Barden notes, and their lifestyles and adaptations are wildly diverse. Some types are vegetarian, while others might dine only on one type of millipede.
Likewise, certain ant species have co-evolved with a single plant species, living in a mutually beneficial symbiosis: the ants may help spread the plant’s seeds or patrol the plants, biting and swarming would-be predators to keep their plant home and food source healthy.
During his four years at RGGS, Barden focused on study of ancient ant species. The early evolution of ants is poorly understood, and Barden and his advisor, David Grimaldi, wanted to find out more. Were early ants social or solitary animals, for instance? And from what lineage of ancient ants did the vast array of modern ant groups evolve?
Early on, Barden traveled with Grimaldi on an expedition to a lignite coal mine in Gujarat, India, to dig for ants fossilized in amber. Lignite is a type of soft coal composed of fossilized plant and other organic material, with seams of fossilized tree resin, or amber, running through it. As the miners worked, the scientists used pick-axes to excavate the amber, which dated to about 50 million years ago.
About that same time, however, a tantalizing find arrived at the Museum. A collector loaned the institution specimens of nearly 100-million-year-old Burmese amber. Enclosed within these specimens were some of the oldest ant fossils known!
These extraordinary specimens suddenly took priority for Barden, who spent much of his time at RGGS—when he wasn’t taking classes or teaching—analyzing the ants within. Using CT scanners from the Museum, Cornell University, and the University of Texas, as well as highly magnified x-ray images from the synchrotron at Argonne National Laboratory, Barden and Grimaldi described a dozen new species of fossil ants.
Barden also generated an evolutionary tree of ants that incorporates these important ancient fossils, and he made key new insights into the early history of ants and the evolution of sociality. That work forms a core part of his doctoral dissertation, which will be published next year.
Today, Barden works in the lab of Professor Jessica Ware at Rutgers University Newark, where he recently began a two-year National Science Foundation Postdoctoral Research Fellowship. There, he aims to further advance his reconstructions of the evolution of ants, integrating both fossil and DNA evidence. And he’ll finally have the time to analyze the 50-million-year-old amber fossils he collected in Gujarat, India, but never had the chance to investigate. What can ancient ants tell us about the world today? With his fossil discoveries and novel research approaches, Barden is finding out.
Growing up in Rio de Janeiro, Andre Carvalho was not always interested in biology—at least not consciously. “It’s so peculiar,” he muses, “when you grow up in Brazil, biodiversity surrounds you, but you may not notice it that much.”
Yet the country’s biological richness was, in retrospect, hiding in plain sight: a friend’s yard might hold fruit trees, for instance, from which you could pick at will.
Throughout his youth, Carvalho had studied hard—his mother promoted academics above all—and was interested in most topics, from history to art to technology. But it wasn’t until college that he realized studying biology would meld all of his interests—he could hone his writing; study the history of life; immerse himself in the beauty of nature; and more.
In college and graduate school, where he received a bachelor’s degree in biology and a master’s degree in zoology, he specialized in the study of lizards. Then Carvalho took up teaching. He taught science for five years in a struggling public high school where he and other teachers helped double the students’ success rate on the national exam.
Having traveled little during his youth, Carvalho hoped to study for the Ph.D. degree in another country, and when he learned about the Museum’s Richard Gilder Graduate School (RGGS), he was sold. Waiting on tenterhooks to hear whether he had been admitted, he received his email of acceptance on the final day of Carnivale, Rio’s biggest and most famous celebration.
“It was amazing, almost surreal,” he recalls.
While at RGGS, Carvalho was supported by a prestigious fellowship from the Brazilian government for his study of lizards, and worked with advisor Darrel Frost, an expert in amphibian and lizard systematics. Carvalho decided to focus on the evolutionary relationships of the Tropiduridae family of lizards, which dwell in many habitats across South America, and are some of the most common and widespread of all reptiles on the continent.
Undertaking extensive fieldwork for his thesis research, Carvalho traveled for six months and trekked thousands of miles through Argentina, Bolivia, Paraguay, and his home country, Brazil. With a chartered airplane, he often searched for lizards in places no scientist had ever been before. “I went to the end of the world to sample my lizards,” he says.
During those months, he observed hundreds of specimens, collecting new species and often observing novel traits among the family. For instance, within one lizard genus he found cases of sexual dichromatism, meaning that the females rather than the males are the more gaudily colored sex, a trait often linked with assertive courtship display in males. Do these brightly hued female lizards demonstrate the same behaviors? Carvalho doesn’t yet know, but he hopes to find out during the next phase of his academic career.
For his doctoral dissertation, Carvalho integrated morphological comparisons and DNA data to revise the evolutionary tree of relationships within the family. “Systematically," he says, “it’s not as well resolved as was thought.” But Carvalho’s analyses of more than 1,000 specimens provide the best picture yet of the ancestry and evolutionary history for this important lizard group.
After graduation from RGGS, Carvalho will return to Brazil. He intends to continue seeking answers to his questions about tropidurid lizards. And he plans once again to teach—perhaps graduate students this time around—so that he may pass along the methods he has learned at the Museum to budding scientists.
“It’s time,” he says, “for me to give back.”
Eugenia Gold can’t remember a time in her life when she wasn’t fascinated by dinosaurs.
“I have liked them since the first memories I have,” she says. “When I was a kid, they started finding all these new dinosaurs in China and in South America.”
Growing up in Maryland, Gold would receive newspaper clippings of the latest South American fossil finds from her relatives in Argentina. Geographically close or not, everyone in her family could see that Eugenia’s passionate interest in dinosaurs was not just a phase.
Guided by this interest, she sought out ways to study dinosaurs in school. During high school the chances were few, but she later began research with paleontology professors in the College Park Scholars program at the University of Maryland. From there, she headed westward to complete a master’s degree at the University of Iowa. When she learned she had been accepted to continue her studies in the Museum’s doctoral program, she recalls, “I was ecstatic!”
While at the Richard Gilder Graduate School (RGGS), Gold worked with advisor Mark Norell, Macaulay Curator of Paleontology and chair of the Division of Paleontology, traveling with him for three weeks on one of the Museum’s famed summer expeditions to the Gobi desert of Mongolia. A storied locale for dinosaur paleontology—the first dinosaur eggs known to science were discovered there by Museum legend Roy Chapman Andrews in 1923—the rocky, open plains of the Gobi still yield treasures for paleontologists.
It was there that Gold unearthed a nest of dinosaur eggs and found a large deposit of sauropod dinosaurs, related to the lineage that gave rise to modern birds. For her it was a magical trip, combining everything Gold appreciates about nature: “camping out, building campfires, finding fossils.”
Back at the Museum, she continued to study dinosaurs, with a focus on their brains. Using various "landmarks" revealed by CT scans of the braincases of fossil theropods and their modern bird descendants, Gold was able to determine how dinosaur and bird brains evolved in size and shape over time. This research formed the basis for a portion of her dissertation, which will be published in the coming year.
“We see an expansion of the forebrain as we get closer [in evolutionary time] to birds,” she says. The brains also become more S-shaped instead of linear, in order to fit those larger forebrains—which are necessary for flight—into the skulls.
Today, Gold is teaching human anatomy to medical students at Stony Brook University. Sometimes, she notes, the designs of our own bodies don’t seem to make sense; often, this odd architecture is retained from, or shared with, the body plans of our ancient vertebrate ancestors. It’s a past that, after decades of interest in, and study of, among the most charismatic of vertebrate groups, Gold is notably well-trained to understand and explain.
During her four years at the Richard Gilder Graduate School (RGGS), Carly Tribull traveled the world. She flew to Gujarat, India; drove up the west coast of the United States from San Diego to Seattle; spent time at the Museum’s Southwestern Research Station in Arizona; camped her way down the east coast of Australia; and visited museums from Brazil to Paris.
Tribull wasn’t on a grand tour, though. Her many road trips were all fieldwork to collect and study wasp specimens. Tribull’s aim while at RGGS was to map the evolutionary relationships within two families of wasps—the Dryinidae and Bethylidae. These solitary wasps are “parasitoids,” meaning the females lay eggs in or on other insects. These eggs then hatch into larvae that feed on the living host, killing it. This quality makes these wasps essential parts of ecosystems and means they serve as biological controls on many agricultural pests. While older evolutionary “trees” of these families were based on shared physical characteristics, Tribull wanted to add molecular genetic evidence, and test whether those traditional relationships held up under more comprehensive analyses.
To do that, Tribull collected numerous wasps during her many expeditions, using so-called Malaise traps (named for the man who developed them, not for a state of emotional ennui), which have a tent-like shape that funnels insects into a collecting vessel. Tribull brought those specimens back to the Museum to perform advanced DNA sequencing, and found that the relationships proposed on purely physical traits did not match her new results.
“When you consider molecular data,” Tribull found, “you don’t get the same findings as the older classifications.”
Tribull used the data she gathered to create new phylogenies for these wasp groups. These trees of evolutionary relationships form the foundation of her Ph.D. dissertation, which she defended in May 2015, advised by James Carpenter. While at the Museum, Tribull also taught Columbia University graduate students how to discover, collect, and identify insects alongside her co-advisor David Grimaldi; and wrote, illustrated, and published a four-part comic series about the lives of a variety of wasps.
A highlight of her time at the Museum, though, was spending time among the millions of specimens housed in the collections of the Division of Invertebrate Zoology. While one might imagine that the collection, which hosts a vast library of ants, bees, wasps, and mollusks (along with other backbone-less animals), to be hushed or frequented only by scientists, Tribull also found it bustling with groups of students that were always visiting.
“The Museum is a great place if you’re interested in informal education,” she says. She relished opening drawers in the collections and sharing the giant katydids, the stickbugs, and more with visitors of all ages.
Recently, Tribull began a two-year visiting assistant professorship at Sam Houston State University, in Huntsville, Texas, where she is teaching zoology and contemporary biology, and continuing her scientific research on wasps. Once she settles in, Tribull plans to start taking students into the field where they’ll learn to identify and collect insects in the region. Hopefully, they too will catch the science bug.
2014 Graduates
Alejandro Grajales’s love affair with the oceans started 22 miles off the Pacific coast of Colombia, on the island of Gorgona.
Then in college, Grajales, who is receiving his Ph.D. in comparative biology from the Museum’s Richard Gilder Graduate School on October 27, was taken on his first SCUBA dive by a group of friends.
Formerly, notes Grajales, Gorgona served as the “Colombian Alcatraz,” an island prison for potentially dangerous offenders. But today it is a national park renowned for its endemic species, found nowhere else on Earth, and Grajales was fascinated by the invertebrates he saw on that first dive—even if the setting, particularly at night, was a bit eerie.
Coming from a family of medical doctors, Grajales, who hails from Colombia, knew he would probably go into science. He studied the biology of corals in college and in graduate school at the Universidad de los Andes, in Bogotá, Colombia. But before coming to the Richard Gilder Graduate School, he conferred with Gilder Assistant Professor and Assistant Curator Estafania Rodriguez and decided to study the evolution of a related group of cnidarians: sea anemones within the genus Aiptasia.
Unspooling the seemingly complex pattern of relationships among species in this group became a goal of Grajales’s time in graduate school. In four years, Grajales travelled widely in pursuit of the sea anemones he studied. A National Science Foundation (NSF) grant brought him from seaside United Kingdom to Cape Verde, Africa, and from Spain to Israel. On each trip he, like many peripatetic researchers, would first telephone scientists working locally, who would often facilitate his research by helping him find boats to dive from and locate the best sites for finding important scientific specimens.
In all, he visited 12 countries during nine field expeditions for his doctoral research. And, happily, his work proved fruitful— yielding many publications and revealing, for one thing, that “what was previously thought to be a group of species might in fact be a single widespread, potentially invasive species,” as Grajales wrote in a blog post about his graduate work on Nature.org.
This month, Grajales will travel once again from Colombia to New York to participate in the commencement ceremonies.
Last summer, Ansel Payne drove 16,000 miles in two months. Traveling from New York City to the deserts of the American West—zigzagging between Arizona, California, Colorado, and Oregon—Payne collected thousands of wasp and bee specimens for his doctoral research.
Since many species are uncommon, Payne, a student in the Richard Gilder Graduate School, mapped out his target sites by first consulting the Museum’s collections to note specific locales where they’d been found before.
This road trip—which included many nights at inexpensive motels or camping in “middle-of-nowhere” places—was just one of Payne’s field expeditions while at RGGS. He also traveled to the Museum’s Southwestern Research Station in Arizona, as well as to Nicaragua and Israel, where he expanded his study of modern groups of solitary bees and wasps.
While bees and wasps are often thought of as social animals—imagine a hive of honeybees—most species are actually solitary and don’t form colonies. Payne studied several of these solitary forms, including the philanthine wasps often called bee wolves, since some species hunt bees to feed their larvae (as adults, they eat mostly flower nectar).
Payne was interested in how these wasps’ behavior was revealed in their evolution over time. For instance, there is at least one group of philanthine wasps that no longer hunts bees; instead they prey on beetles, and evolved adaptations allowing them to do so effectively. As Payne explains, females from one beetle-eating group have horn-like structures on the fronts of their faces. These help females more easily carry the heavy beetles to their nests after stinging them, where their larvae later eat the paralyzed insects.
“Life is really old,” says Payne, explaining what drew him to the study of comparative biology. “And it has this mysterious backstory we don’t know much about.” But, he adds, we have a “few methods that allow us to recreate it as best we can.”
Payne, a former high-school biology teacher, studied biology in college at Harvard University and for his master’s degree at Tufts University. Meanwhile, the thousands of wasp and bee specimens Payne collected in the field have become part of the Museum’s research collection—clues for other researchers searching for the mysterious backstory of life.
Passionate about lizards and frogs, Pedro Peloso, who will receive his Ph.D. degree from the Museum’s Richard Gilder Graduate School on October 27, lost no time between defending his dissertation and diving back into researching the biodiversity of his home country, Brazil.
Within a week of defending his dissertation this September, he became a “Science without Borders” Postdoctoral Fellow at the Museu Paraense Emílio Goeldi.
But first came the dissertation defense, a highlight of Peloso’s time as a graduate student. “My work dealt with the phylogenetic relationships of narrow-mouthed frogs (Microhylidae), and I also studied the evolution of reproductive modes in these frogs,” says Peloso. But it wasn’t so much the subject matter as the people who were there to see him defend his work. “It was very emotional,” says Peloso, “with a room full of people—friends, teachers, family, curators, and science enthusiasts—interested in learning a little bit about all that I have done in the last four years.”
Other high points of his time in the Museum’s innovative graduate school were the research travels, says Peloso, who conducted extensive fieldwork in Vietnam and Brazil and worked with collections and in labs in the United Kingdom, Germany, India, and Australia. During those trips, Peloso collected data for his doctoral work but also was lucky to find a few undescribed species of frogs, which he continued to describe as part of his post-doc.
Growing up near the beaches of Los Angeles, California, Dawn Roje never thought she’d enter academia. But passions for SCUBA and the oceans, along with an inspiring ichthyology professor at the University of California, Los Angeles, ultimately led her to the Richard Gilder Graduate School Ph.D. program in comparative biology, where she focused on flatfishes, a large group of about 650 species that includes food-fishes such as halibut, flounder, sole, and fluke.
Fascinated by the seemingly bizarre characteristics of flatfishes—their elongated fin rays, the migration of their eyes to a single side, and skin pigment cells organized in complex arrays—Roje took on the problem of studying the origins and evolutionary transformations of these features, including what she describes as the “mechanism of one of the most amazing body plan transformations in biology.” (The title of Roje’s dissertation is "Molecules, Morphology and Monophyly: Resolving Flatfish (Pleuronectiformes) Phylogeny and Investigating Why it Has Been So Difficult to Do.”)
Her research took her to Southern California, Mexico, and, in 2013, to the Solomon Islands on the Museum’s 2013 Explore21 Expedition, where Roje managed the lab on board the R/V Alucia in addition to collecting larval and adult forms of eels, flatfish, and jacks for her dissertation.
“Finding treasures during my first two days out at sea is an odd mix of exhilaration and calm,” she wrote from the Solomon Islands last September. “Exhilaration in finally obtaining the specimens I crossed the dateline for, and reassuring in that anything else I collect beyond this point is an excess of riches.”
As a Ph.D. candidate, Roje was awarded a U.S. National Science Foundation Doctoral Dissertation Improvement Grant, as well as the Richard Gilder Graduate School’s Lerner-Gray Grant for Marine Research.
Roje, who taught high school science after college, continued to teach while completing her Ph.D. She taught a course on the Tree of Life in the Museum’s After School Program for high school students, served as a teaching assistant for an Evolution course at Barnard College/Columbia University, and mentored a high school student who was writing a thesis on DNA barcoding identification of leiognathid ponyfishes.
2013 Graduates
Though John Denton grew up in Gainesville—“about as far as you can get from the beach” in Florida—he’s always been interested in marine life.
So it makes sense that while working toward his Ph.D. degree from the Richard Gilder Graduate School, from which he will graduate September 30, Denton studied deep-sea fishes called lanternfishes and the evolutionary relationships between the different species.
Lanternfishes are bioluminescent, meaning they generate light through a chemical reaction within their own bodies. They also “compose most of the biomass in the deep sea,” Denton says, noting that these small but fascinating fishes have the most elaborate bioluminescent systems of any deep-sea organism: not just a headlight, but also body photophores, or light-emitting organs, arranged in rows along the body and, in certain species, bioluminescent tail-organs called stern-chasers that produce a flash of chemically created light, perhaps to distract predators as the fish darts away.
A graduate of Harvard, Denton received his master’s degree from Stanford University, where he studied quantitative methods he would later apply to his work at the Museum.
His Museum adviser, Richard Gilder Graduate School professor Melanie Stiassny, says “he has done the most recent morphological work on lanternfishes,” while using quantitative and molecular methods—“math, molecules, and fish,” he jokes—to round out the analysis.
In order to study lanternfishes, which are found in oceans around the world, Denton also conducted fieldwork in the Pacific: he joined a team from the Pacific Islands Fisheries Science Center (National Oceanic and Atmospheric Association [NOAA]) aboard a ship off the Kona Coast of the Big Island of Hawaii, where they trawled at night from dusk to dawn, gathering deep-sea organisms including lightfishes, dragonfishes, cookie-cutter sharks, and more, in their nets. Denton also spent time trawling off the coast of American Samoa with NOAA; in addition, he studied fossils of lanternfishes in various museums, including the Natural History Museum of L.A. County.
In his Idaho elementary school, Bryan Falk was regularly sent to the principal’s office.
Not for passing notes or being tardy, but for getting too close to the off-limits irrigation ditch at the back of the schoolyard.
During recess, Falk couldn’t resist catching garter snakes and tree frogs and sneaking them back home in his lunchbox. By the time he graduated high school, Falk kept a substantial reptile and amphibian collection, was active in his local herpetological society, and had plans to attend veterinary school. But during college, a study-abroad course in Costa Rica on tropical ecology redirected his career path toward scientific research, in particular, the study of parasites.
“I was an undergrad when I learned that lizards got malaria, which I thought was really neat, and I realized that Caribbean anole lizards and their malarial parasites would be a good system to work on,” says Falk. As part of the first class in the Comparative Biology doctoral program at the Richard Gilder Graduate School, Falk spent four years exploring these parasites under the guidance of Susan Perkins, an associate professor in RGGS and an associate curator in the Museum’s Division of Invertebrate Zoology and Sackler Institute for Comparative Genomics.
“Parasites are really common—about a third of all living animals are parasitic—but we don't have a good understanding of how all those species came about,” Falk said.
The goal of Falk’s dissertation research was to better understand parasite diversity. This included collecting new specimens during fieldwork in locations including the Dominican Republic, Madagascar, Mexico, and Florida, and investigating how parasites with different modes of transmission give rise to new populations and species. His research suggests that multiple factors contribute to parasite diversification and that the great variation in parasite traits—such as life cycle complexity and number of hosts—begets species diversity.
“I showed that the pattern of diversification in a widespread lizard malaria parasite group is very similar to the unusual patterns observed in a human malaria parasite,” Falk said. “These patterns were once considered to be the result of coevolution with us, the parasite’s hosts. Instead, my research suggests that malaria parasite diversification is shaped through the parasites’ life cycle and low prevalence, and that malaria parasites of wildlife may serve as models to study the evolution of those affecting humans.”
Falk received his bachelor’s degree in biology from Portland State University.
Antonia Florio spent her childhood in Queens, New York, “saving” flies that flew into her apartment.
She generally adored living things, and though she wanted to be a veterinarian, she eventually gravitated toward biological research instead.
The class of 2008 valedictorian of the City College of New York (CUNY), where she was also a member of Macaulay Honors College, Florio first came to the Museum as an undergraduate on a National Science Foundation-sponsored Research Undergraduate Experience (REU). “That was the first time I realized that the Museum was more than a public space—it was also a research institution,” she says.
Florio returned as a graduate student in 2008, working closely with her adviser, Richard Gilder Graduate School Associate Professor Chris Raxworthy, who is an associate curator in the Department of Herpetology and has been traveling since 1985 to the island of Madagascar to study reptiles and amphibians. Though as an undergraduate Florio had studied beetles and fishes, she happily switched to chameleons, many species of which are found only on that island. Spending months doing fieldwork in Madagascar, she says, “I did so many things for the first time: catching a chameleon; speaking French; dealing with permits—in French!” Other fieldwork while at the Richard Gilder Graduate School included coursework studying parasites in Mexico with Mark Siddall, curator in the Division of Invertebrate Zoology.
But Furcifer lateralis, or the “carpet chameleon,” of Madagascar—so named for its color patterns resembling sumptuous Persian carpets—became her focus. For her dissertation, she used genetic, morphological, and environmental data in order to better understand how new species are formed. She was also able to determine that the three species of Furcifer chameleons she’d studied in Madagascar, actually represented a complex of seven distinct species.
Growing up in the seaside city of Helsingborg, Sweden, Sebastian Kvist was fascinated by water—and the living organisms in it.
Kvist, who remembers spending much of his childhood staring at the exotic offerings of local fishmongers, credits his love of science to his parents, who encouraged heated debates at the dinner table, but only if they were backed by actual observations.
“I enjoyed these discussions and, in retrospect, I can see how they shaped my critical thinking,” Kvist said. “It might come as no surprise that both my mother and my only brother hold Ph.D.s in obstetrics and gynecology and cell and molecular biology, respectively.”
Having studied marine oligochaetes (relatives of earthworms) as an undergraduate, Kvist began the journey toward his own Ph.D. in 2008, when he came to the Museum as part of the first class in the Comparative Biology program at the Richard Gilder Graduate School. Over four years, he studied organisms ranging from bacteria to perplexing groups of oceanic invertebrates, using microscopy and advanced imaging and DNA sequencing techniques.
The author of 11 scientific publications while in graduate school, Kvist wrote his thesis about the evolutionary relationships of segmented “worms”—bristle worms, earthworms, leeches, and their close relatives, all called annelids—and the symbiotic relationships that some have with bacteria.
Kvist focused primarily on medicinal leeches, which have adapted to feed exclusively on blood via the evolution of extremely potent anticoagulants, or blood-thinners.
In addition to being important from an evolutionary standpoint, studying how leeches circumvent the blood-clotting mechanisms of their hosts could be used one day to develop anticoagulants and tumor inhibitors in humans. Mark Siddall, then professor at the Richard Gilder Graduate School and curator in the Museum’s Department of Invertebrate Zoology who is one of the world’s most authoritative experts on leeches, was Kvist’s advisor.
Kvist conducted much of his research during field expeditions to Mexico (pictured below), Canada, Sweden, and Washington and New Jersey in the U.S.
“Most people think that leeches only occur in stagnant foul-smelling swamps or polluted waters but this couldn't be further from the truth,” Kvist said. “Leeches normally need clean, and sometimes flowing, water. That said, some of the places where we've looked for leeches are no place to go for vacation. I have been waste-deep in stagnant lakes in several places on several continents.”
Prior to enrolling at the Richard Gilder Graduate School, Kvist received a bachelor’s degree and master’s degree in biology from Sweden’s University of Gothenburg and a certificate in conservation biology from Lund University, also in Sweden.
Growing up in Ridgefield, Connecticut, Shaena Montanari had always been interested in science, and she loved taking the train to New York to visit the Museum for field trips. When she returned to the Museum years later as a graduate student at the Richard Gilder Graduate School her research took her much farther from home—including to Mongolia’s Gobi desert—to uncover fossils of long-extinct animals.
A member of RGGS’s first-ever class, which matriculated in 2008, Montanari used innovative techniques, including measuring the ratios of stable isotopes of carbon and oxygen in eggs, bones, and teeth of fossil vertebrates, in order to analyze the extinct animals’ diets and ecology, as well as nature of climates in which the animals had lived—known as paleoclimates.
As part of her degree studies, she conducted fieldwork in Wyoming; Canada; and, twice, in Mongolia, as part of the Museum’s annual expeditions to the Gobi desert, which started in the late 1910s under Museum fossil-hunter Roy Chapman Andrews and, after a hiatus due to political turmoil, resumed in 1990.
“To be a part of the Gobi expedition is a huge honor,” says Montanari, though the way she joined the trip was fairly low-key. “During my first year,” she says, her advisor “Mark Norell stopped by the student lounge and asked me, ‘So, do you want to go to Mongolia?' …”
While there, Montanari collected oviraptorid dinosaur eggshell-fragments and teeth from a famed fossil locality called Bayn Dzak (the Flaming Cliffs) to examine stable isotope ratios in these 80-million-year-old fossils. Because Montanari’s technique is to grind portions of the fossils to conduct her research, she collects broken pieces, not intact specimens.
In addition to time spent in the field, says Montanari, “I’ve learned so much—and grown leaps and bounds!” A grantsmanship course—required for all students—provided hands-on structural help for writing and improving grant applications and scientific articles. (While a graduate student, Montanari received the National Science Foundation’s prestigious Graduate Research Fellowship.) “From the day we got there, the faculty emphasized writing—how to write papers, apply for grants,” says Montanari, who published several research papers while in school.
There are only 12 species of reptiles and amphibians native to Great Britain.
Edward Stanley did his best to catch them all during his childhood in the Dorset countryside.
So it may be no surprise that Stanley, a member of the second entering class (2009) in the Comparative Biology doctoral program at the Richard Gilder Graduate School, continues to collect and study these animals.
Stanley’s dissertation focused on the evolution of armor in the Cordylidae, a family of diverse girdled lizards in southern Africa. The lizards’ armor is actually made of tiny bones embedded in their skin, called osteoderms, which are thought to protect the animals from attacks by predators.
“I worked on the evolutionary relationships of this group during my master’s degree, and the more I learned about them, the more interesting questions came to mind,” Stanley said. “It was amazing to me how little was known about these fascinating animals, and so I decided to delve deeper into their evolution.”
Osteoderms are embedded into the lizard’s skin, not attached to the skeleton. To measure and analyze the variation in these bony plates of armor in place, Stanley used high-resolution X-ray computed tomography (CT) in the Museum’s Microscopy and Imaging Facility. He took full-body scans of the more than 80 living and extinct species in the family. Stanley found that these lizards underwent a period of rapid diversification during the Oligocene-Miocene boundary, about 23 million years ago, a diversification linked to ecological adaptation.
Stanley also described a new species of girdled lizard, Cordylus marunguensis, found in the mountains of central Africa, and revised the taxonomy of the family, naming several new genera, including Smaug—for their resemblance to mythical dragons—and the tail-biting Ouroborus.
Stanley, who was advised by Curator Darrel Frost, conducted fieldwork throughout southern Africa, including South Africa, Lesotho, and Swaziland, where collecting lizards wasn’t always risk-free, involving climbing waterfalls, avoiding venomous snakes, and dealing with rapid weather changes.
“In Lesotho, we had to quickly get to lower ground as a giant lightning storm rolled in,” Stanley said. “It was pretty scary because we were walking around on one of the highest points in southern Africa—with metal crowbars tied to our backs!”
Stanley received his bachelor’s degree in zoology from the University of St. Andrews in Scotland and his master’s degree in biology from Villanova University.
Throughout her life, Isabelle Vea has lived in and travelled to many exciting places.
Among the first students to graduate from the Museum’s Richard Gilder Graduate School, Vea grew up and attended college in Paris, where she also received a master’s degree from the famed Muséum National d’Histoire Naturelle; studied Mandarin Chinese in China for a year; and has spent the past four years in Manhattan, analyzing scale insects at the Museum.
Belonging to the order Coccoidea, scale insect species living today number about 8,000; they are often crop pests, but little has been known about their evolution. For her dissertation, Vea produced a timed phylogeny—that is, a “tree” of evolutionary relationships placed within a time scale—of the superfamily, the first such assessment of the relationships between fossils and recent species in scale insects.
As part of the work, Vea worked with her adviser David Grimaldi, a professor in the Richard Gilder Graduate School and curator in the Division of Invertebrate Zoology, to study the evolutionary relationships of both living species and extinct forms of a smaller group of coccoids, the family Ortheziidae, some of which are about 95 million years old and have been preserved in amber. Among fossil scale insects, males of the species are more likely to fossilize, but in this particular family, the females were preserved in the fossil record.
Prior to conducting her research, Vea hypothesized that scale insect species might have diversified starting at the same time—about 130 million years ago—as the flowering plants (angiosperms) that living scale insect species feed on today. Instead, however, “Isabelle's work found that the group largely diversified before the angiosperms did...” notes her adviser, David Grimaldi. “Scales must have evolved with conifers and other gymnosperms, then shifted onto angiosperms—an insight that could only be derived from study of the fossil record.”
In addition to studying the Museum’s exceptional amber collections, Vea conducted her own fieldwork collecting modern specimens in France, Croatia, Florida, and New Mexico, as well as at the Museum’s Southwestern Research Station, in Arizona. For Museum coursework, she also travelled to Costa Rica and Mexico.
Fall 2025 Comparative Biology Ph.D. Program Enrollment
Next application deadline: December 15, 2024
Important Notes:
RGGS has eliminated the GRE test requirement for Comparative Biology PhD admissions and partner institution Graduate Fellowships. We will not accept GRE test scores or consider them in our evaluation process.
Applicants for partner institution Graduate Fellowships: be aware that each partner institution will have its own testing requirements and may or may not require GRE scores for their applications. Be sure to check and comply with their admissions requirements in your application(s) to the partner universities.
Requirements:
- Bachelor of Arts or Bachelor of Science or equivalent degree, from an accredited institution
- Applications will be accepted from students who have completed some graduate work or an advanced degree at another institution. All applicants, however, will be required to complete the core courses of the RGGS program, regardless of their prior background.
- Official transcripts: from all undergraduate/graduate institutions attended
- Three letters of support: from instructors, research advisors, or other mentors
- Statement of Academic Purpose-two essays: description of research interests/experience
- Interview: final candidates will be interviewed
- Faculty sponsor: Through student contact or assigned by the AMNH
- Application fee of $50: Required with the Comparative Biology Ph.D. Program application; non-refundable
- Proficiency in English:
- TOEFL or IELTS (Academic Exam) scores are required for non-native English speakers unless they have earned a graduate or undergraduate degree in a program using English as its official language of instruction. TOEFL or IELTS tests must have been taken within the past 2 years.
- TOEFL scores generally must total 600 or higher, typically with 60 or greater on each subsection (PBT), or total 100 or higher, typically with 25 or greater on each subsection (iBT). Get more information on TOEFL.
- IELTS scores must be at least 7.0 in total. Get more information on IELTS.
Submission of Application
The application for admission, together with supporting materials must be uploaded online through the admissions portal.
Please note that all applications and supporting materials become the property of the Richard Gilder Graduate School. Since the applicant is responsible for sending official transcripts to the RGGS in sealed envelopes and securing letters of recommendation, it is important that the applicant requests supporting documents as early as possible, to ensure that all supporting materials are secured well in advance of the application deadline.
Applicants are strongly encouraged to contact a member of the faculty prior to application. Final candidates will be invited to the Richard Gilder Graduate School for interviews, whenever possible. The interview process represents the graduate school’s commitment to finding students that will most benefit from and contribute to the Ph.D. Comparative Biology program. It also enables the Graduate School faculty to make the very best matches between students and faculty advisors - part of the Richard Gilder Graduate School’s deep commitment to personal advising, mentorship, and guidance of students.
Application Fee
There is a non-refundable application fee of $50 if you are applying to the RGGS Comparative Biology Ph.D. Program. You must pay this fee before your application will be processed. Specific directions will be provided when you reach the end of the application and are ready to submit.
Note: Our application fee should not discourage any student from applying to RGGS. If you feel the application fee will represent a substantial financial burden, please request a waiver by email to: [email protected] as soon as possible. If you request a waiver you will not be able to submit your application online until after it is approved.
View the Notice of Non-Discrimination from the American Museum of Natural History.