Ph.D. Graduates: 2023
Alumni of the comparative biology program hold positions in science, academia, education, and museums around the world. Here are the four doctoral graduates of 2023.
Alexandra Grace Walling
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.
Nayeli Gutiérrez Trejo
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.
Hollister Wade Herhold
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.
Fall 2024 Enrollment
Next application deadline: December 15, 2023
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.
- 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.
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.
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.