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Delicate, with the eerie beauty of a 19th-century engraving, the gray-and-white cross-section of Nautilus pompilius — an object of ongoing research by Museum paleontologist Neil Landman – is the product of a cutting-edge, high resolution, computed tomography (CT) scanner. Acquired by the Museum last summer with a grant from the National Science Foundation, the GE Phoenix V/tome/x Dual-Tube CT Scanner is one of only four of its kind in the country and allows researchers to look deep inside both small and large specimens without destroying them in the process.
“We can see spatial detail not available in dissection, and some parts are so delicate they would be otherwise missed,” says Dr. Landman, curator in the Division of Paleontology who, with geologist Denton Ebel, associate curator in the Division of Physical Sciences, and Curator Darrel Frost, a herpetologist, wrote the successful grant application for the scanner. “Three-dimensional visualization is such an important part of our thinking now—you can put your arms around the object you are studying.”
For each image, the scanner, as a rule, takes 1,500 to 1,700 x-ray images as the sample is rotated in the x-ray beam, at a level of resolution 100 times that of a typical medical scanner used on humans. These images are then used to create a 3D image of the entire specimen—in essence, a stack of virtual dissection slices—that can be manipulated, rotated, and studied from every angle, revealing unprecedented details of its internal structure. “We can only capture so much of the morphology from the surface,” explains Landman. “You want to get insights into the interior.”
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After the Museum closed on Thursday, March 3, tweeters gathered beneath the towering Apatosaurus and Tyrannosaurus rexin the Hall of Saurischian Dinosaurs for the Museum’s Dinosaur Tweetup. Choosing from a slate of tours, groups of tweeters headed to behind-the-scenes destinations for a conversation with one of the Museum’s scientists, a preview of a major upcoming exhibition, and a close look at some of the specimens in the collections,
In his office on the Museum’s off-limits sixth floor, paleontologist Mark Norell, co-curator of the upcoming exhibition The World’s Largest Dinosaurs and chair of the Division of Paleontology at the Museum, met with tweeters to discuss his current research and show an unnamed fossil specimen.
Tweeters also visited the Exhibition Design Studio to see the preparations underway for The World’s Largest Dinosaurs, which opens April 16. Senior Vice President for Exhibition David Harvey revealed the partially constructed model of a Mamenchisaurus, which will reach 60 feet in length. Tweeters also got a glimpse of a colossal sauropod femur and of the exhibition in miniature.
Finally, in the Big Bone Room, paleontology collections manager Carl Mehling told stories of dinosaur-hunters of the past and presented some of the largest items in the Museum’s collection. Highlights included a look at a fossilized dinosaur brooding eggs and the chance to touch a 70-million-year-old impression of dinosaur skin.
Read more about the tweetup in these posts from participants @alana_margaret and @anthinpractice, find out what tweeters had to say by following the #AMNHTweetup hashtag, and check out the photos on Flickr. Follow @AMNH on Twitter for more news from the Museum and stay tuned for information on upcoming tweetups and other events.
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After flying nearly 5 billion miles over six years, the MESSENGER spacecraft is scheduled to begin orbiting the innermost planet. On Thursday, March 17, join Denton Ebel, associate curator in the Museum’s Department of Earth and Planetary Sciences, and Joe Boesenberg, senior scientific assistant in the department to watch a live feed from MESSENGER operations center at Johns Hopkins University and hear about new information that has been gleaned from the mission so far, such as the importance of understanding the planet’s high-density composition.
To date, three flybys of Mercury have yielded insights into this least explored terrestrial planet, starting with a historic flyby in January 2008. The Museum’s Science Bulletins chronicled the MESSENGER science team’s reaction as the orbiter’s first images of Mercury rolled in. Click below to watch the Science Bulletins video feature. For more about the MESSENGER mission, check out the article, “First Planet Finishes Last.”
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To walk the fourth floor of the Museum — peering at the jagged “teeth” of armored fish Dunkleosteus, ducking under the 23-foot wingspan of the flying reptile Pteranodon, studying the long curved tusks of the elephant relative Mammuthus — is, in a sense, to walk the tree of life.
Each branching point represents the arrival of an evolutionary innovation — jaws, water-tight eggs, hooves, respectively — that unites one group of animals and distinguishes them from lineages that lack the feature. Known as synapomorphies, or shared traits derived from a common ancestor, these are the tracks of evolution.
Scientists have used trees to order life since before Charles Darwin first scribbled a spiky diagram in his notebook. In the 1950s, German biologist Willi Hennig formally proposed that trees of life should reflect evolutionary relationships among organisms, founding cladistics: a method for grouping organisms into ancestor-descendent clades, from the Greek word for “branch,” based on shared, derived features. But it took a Museum scientist, ichthyologist Gareth Nelson, to disseminate the idea among English-language biologists. Together with students and colleagues at the Museum — including another ichthyologist, Donn Rosen, paleontologists Eugene Gaffney and Niles Eldredge, ornithologist Joel Cracraft, and invertebrate specialists Norman Platnick and Randall T. Schuh – Nelson steadfastly argued the case for cladistics as the tool to test classification during academic talks, in research papers, and even on napkins over meals.
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Medicinal plant use thrives even in urban centers like New York City. At the upcoming SciCafe on Wednesday, March 2, Dr. Ina Vandebroek of the Institute of Economic Botanyat the New York Botanical Garden will discuss the role of medicinal plants in primary healthcare among indigenous peoples in the Bolivian Amazon and immigrant communities in New York City. She recently answered a few questions about her upcoming talk.
What is ethnobotany, and how is it practiced?
Ethnobotany is the science that documents how people perceive, manage, and use plants for healthcare, nutrition, clothing, construction, tools, ritual and social life. An ethnobotanist is part anthropologist and part botanist. He or she shares life in the field with local community members, conducts interviews, and collects the plants that are mentioned by participants to make herbarium specimens that cross-link common plant names with botanical plant names.