Yale Community

Description:
The Communications Office of the Peabody Museum seeks an intern interested in pursuing a research question that lies at the heart of our historic collections: “Why does the object matter?” With high-resolution photography, CT scanning, 3-D printing, and NFTs, are the >14 million items occupying the museum’s shelves and cabinets becoming obsolete? How do the material and human histories give the “object” a unique value, and how does uncovering those histories offer insight into collecting practices, contemporary scientific research, and the future of museums? What does an encounter with the actual object offer a researcher, student, or museum visitor?

Research will involve object analysis (e.g. measurements, chemistry, etc.), consultation with collection staff and/or available primary sources (e.g. field notes, interviews, etc.), and citation and exhibition history. Working in collaboration with staff and curators, the investigation of these questions will yield meaningful archival information and fascinating content that can be shared with the Peabody’s growing community of followers and families via social media, the museum’s website, and on its YouTube channel. The project will culminate with an essay and a public presentation for a live audience.

Timeline:
Weeks 1-2
    •    Object(s) identification
    •    Work with Collection Managers to identify an appropriate object or set of related objects.

Weeks 3-7
    •    Research and content production
    •    Conduct interviews
    •    Consult primary sources and Peabody Museum archive
    •    Complete thorough literature review and citation history
    •    Create visual and written content with assistance from communications team

Week 8
    •    Editorial and presentation preparation
    •    Receive and incorporate feedback from communications and editorial staff
    •    Finalize presentation

Deliverables:
6-8 social media posts
1 final essay with multimedia (video/photos)
1 public presentation

Connection to YPM Collections:
The participant will work directly with collections staff to identify appropriate objects and research their history through interviews, archival information, associated publications, etc.

Advisor
Chris Renton, Associate Director of Communications and Marketing

Length: 8 weeks

Stipend: $3,800

Project Description:
Salamanders are exceptionally diverse in the habitats they occupy and their life history. These differences have allowed them to occupy different ecological niches and to utilize different feeding modes (e.g., suction feeding, tongue protrusion). These differences in feeding modes are, in turn, adaptive shifts in cranial and hyobranchial morphology. The goal of this project will be to collect and analyze skeletal and musculature data and compare differences in morphology to better understand the evolution of salamander feeding systems.

The YPM intern will learn how to collect morphological data from museum specimens available at YPM. Interns will have the opportunity to prepare specimens to be micro-CT scanned for 3-D visualization. Scanning will be conducted by Henry Camarillo, but the intern may observe and assist with the process. Interns will have the opportunity to post-process micro-CT scans and collect morphometric data from the salamander cranium and tongue skeleton. The intern will be trained to analyze the morphological data through statistical and evolutionary methods utilizing the R programming language. Specifically, the intern will combine data they collected with morphometric data previously collected by the Muñoz lab and learn how to do comparative evolutionary analyses between salamander species.

This project has the potential to lead to a continued undergraduate research position in the Fall semester, senior thesis project, presentation at conferences, and/or publication in peer-reviewed journals.

Advisors:
Dr. Martha Muñoz (Assistant Professor of Ecology & Evolutionary Biology; Assistant Curator of Vertebrate Zoology, Yale Peabody Museum of Natural History)
Henry Camarillo (Graduate Student of Ecology & Evolutionary Biology)

Outcomes:
The intern will be encouraged to publish a peer-reviewed paper in a scientific journal. In addition, the intern will have the opportunity to present work at the 2024 northeast regional and/or national meeting of the Society for Integrative and Comparative Biology (SICB 2024 in Seattle, WA).

Connection to YPM Collections and Departmental/Divisional Goals:
This work will directly use specimens available in the Vertebrate Zoology (Herpetology) collections, with supervision and assistance of Sr. Collection Manger, Greg Watkins-Colwell. In addition, scan data will be uploaded to the Peabody Museum Collection Management System and eventually made available to online public outlets, which helps other researchers access data from natural history museums.

Length: 8 weeks

Stipend: $3,800

Project Description:
Cypriniform fishes (minnows, carps, and bitterlings) are a species-rich group that comprise more than 13.5% of all ray-finned fishes. Cypriniforms are distributed in freshwater habitats in Eurasia, Africa, and North America and display a wide range morphologies, reproductive strategies, and adaptations to different habitats. The phylogenetic relationships among the major lineages of cypriniforms are unresolved, limiting the reconstruction of their evolutionary history. This project will involve the collection of a genomic-scale DNA sequence dataset for a set of species that represent the major lineages of cypriniforms. The project will involve the construction of genomic libraries, the use of bioinformatic tools to infer phylogenetic relationships from genomic-scale datasets, and the use of information from the fossil record to build relaxed-molecular clock time trees.

Thomas J. Near will supervise this work along with EEB graduate students Ava Ghezelayagh and Julia Wood.

It is likely this project will result in at least one scientific paper and could very well become a senior thesis project for a Yale undergraduate student.

This project will utilize collections resources present in the Division of Vertebrate Zoology.

Length: 8 weeks

Stipend: $3,800

Description:
Eastern North America contains the most species-rich freshwater fish fauna among temperate regions of the world and is also a hotspot of biodiversity for crayfishes. The Central Highlands are a set of disjunct areas that are hypothesized to contribute to the high aquatic biodiversity of North America. This project will involve the estimation of phylogenetic relationships, assessment of morphological diversity, and delimitation of species in the charismatic Banded Darter (Etheostoma zonale) and a lineage of crayfishes that are both endemic to the Central Highlands. The project will involve the construction of genomic libraries, the use of bioinformatic tools to infer phylogenetic relationships from genomic-scale datasets, and the collection and analysis of morphological data to delimit species. There will be a field trip to the different regions of the Central Highlands to augment holdings of tissues and whole body specimens at the Yale Peabody Museum.

Thomas J. Near will supervise this work along with EEB graduate students Ava Ghezelayagh and Julia Wood.

It is likely this project will result in at least one scientific paper and could very well become a senior thesis project for a Yale undergraduate student.

This project will utilize collections resources present in the Division of Vertebrate Zoology.

Length: 8 weeks

Stipend: $3,800

Advisors:
Professor Eric Sargis (YPM Curator of Vertebrate Paleontology and Vertebrate Zoology)
eric.sargis@yale.edu
Graduate Student Spencer Irvine (YPM VP)

Project Description:
Undergraduates are invited to participate in morphological research during the summer of 2023 to work with a curator and graduate student from the Yale Peabody Museum (YPM). This project focuses on the adaptive morphology of the primate hip and knee, anatomical regions that are particularly relevant to leaping ability. Leaping is an important locomotor behavior for extant primates, enabling them to traverse their arboreal habitats, and many fossil primates are hypothesized to have also employed leaping behaviors. Although several morphological features have been associated with broad locomotor categories in primates, the relationship of these features to leaping frequency is not well understood.  

This project will apply quantitative morphometric analyses to correlate primate hip and knee morphology with frequency of leaping. These correlations will aid reconstructions of fossil primate locomotor behavior; we cannot directly observe the relationship between leaping and skeletal morphology in fossil primates, but we can use extant taxa as models by comparing the morphology of their hip and knee to that of early fossil primates. This work will help test hypotheses about early primate locomotor behavior and enhance our understanding of primate origins and functional morphology. The project will include a large, diverse sample of primate specimens from museums across the country, and it will build upon an existing dataset of extant and fossil primates. The undergraduate researcher will assist with these analyses in a laboratory setting on campus.

The undergraduate researcher will be involved in multiple aspects of this project. They will learn to use anatomical characteristics to identify and describe primate taxa to address questions such as 1) what is the morphological diversity of primate hind limbs, 2) which skeletal features in the hip and knee best correlate with leaping frequency, and 3) how does phylogeny affect locomotion? The researcher will also learn how to post-process micro-CT scans of these specimens, generate three-dimensional models from the scans, and measure functionally informative features of primate hips and knees from both photographs and 3-D models. The researcher will learn how to conduct statistical analyses in R using the data collected during the internship. Hence, the researcher will have the opportunity to learn post-processing techniques and methods of morphometric data collection and analysis. This project could lead to an expanded senior thesis project, a presentation at a professional conference, and/or a publication in a peer-reviewed journal.

Collaborative presentation with previous summer intern (in bold):

2023: Irvine, SW, Zhang, AL, and Sargis, EJ. Correlating leaping frequency with primate hip and knee morphology. To be presented at the 2023 Meeting of the American Association of Biological Anthropologists.

Length: 6 weeks

Stipend: $2,850

Description:
Fire is increasingly understood as an important ecosystem process, not just in the scientific literature, but also in the media and public imagination. Parts of the conversation are accurate: in some contexts, especially where it represents a threat to human lives and livelihoods and also where it adds new carbon fluxes to the atmosphere, fire is problematic. However, fire is also an ancient and natural element of many ecosystems on Earth, including savannas, and a useful and widely used tool by humans in their interactions with natural systems. Unfortunately, the public conversation about fires largely misses this nuance.

This proposed project will engage with preparing a museum exhibit that nuances public engagement of the role of fire in the Earth system, to be developed for display both at the Yale Peabody Museum (YPM) and subsequently, in modified form, at the Natural History Museum of Utah (NHMU). The mission of the YPM is to advance the public’s understanding of Earth history through geological, biological, and anthropological research, and by communicating this research to the widest possible audience through publication, exhibition, and educational programs. Drawing approximately 150,000 visitors per year, YPM programs are aimed at a diverse audience. The Peabody Museum is located in New Haven, and the greatest user is the New Haven Public School (NHPS) District, a federally defined high-needs district, and the museum offers (as of 2022) free admission. With an average of 300,000 visitors per year and strong ties to eight federally recognized tribes in Utah, the mission of the NHMU is to illuminate the natural world and place of humans within it. As the designated state museum of natural history, the NHMU serves people in communities across the urban and rural landscape by providing access to its collections and, through them, communicating the importance and value of the natural world, and providing key educational services statewide to develop a science-literate workforce.

The YPM exhibit will include 2 cases with drawers to hold specimens such as herbarium sheets (e.g., serotinous Banksias, which depend on fire for reproduction), tree cross sections showing fire scars, and hypsodont herbivore teeth, as well as video and additional supporting media. The intern will be involved in researching the exhibit theme, selecting and handling specimens for display, preparing exhibit text and content, advising on exhibit layout, and editing video to accompany the display cases. The exhibit will have a planned duration of 3 months at YPM in early 2024. The exhibit is targeted as the product of collaboration by two 2 undergraduate students, one based at Yale and the other at Utah, via funded summer internships. Travel to collaborate at UU/NHMU may be appropriate.

Advisors:
Carla Staver (Associate Professor of Ecology and Evolutionary Biology, Yale University)
Tyler Faith (Associate Professor of Anthropology, University of Utah; Curator of Anthropology, Natural History Museum of Utah

Outcomes:
We expect this internship to culminate in a museum exhibit in early 2024 to coincide with the opening of the renovated YPM. The intern should include any of the work they produce in a portfolio/CV, and participation in the exhibit can be translated into a senior thesis project where appropriate.

Connection to YPM Collections and Departmental/Divisional Goals:
The YPM exhibit will source specimens including herbarium sheets (e.g., serotinous Banksias, which depend on fire for reproduction) and hypsodont herbivore teeth from YPM collections, in collaboration with Patrick Sweeney (Senior Collections Manager, Division of Botany). The exhibit is public facing and will contribute to YPM’s outreach mission.

Summary of Potential Costs:
Travel costs will be covered with available funds.

Any Restrictions on Timing:
Staver will be traveling in Brazil in June, so the internship should start in July.

Stipend: $3,800

Description:
SARS-CoV-2 is maintained in humans with repeated but rare spillover events into a very broad range of animals, many of which are able to support conspecific viral transmission. Proactive monitoring of potential spillover of SARS-CoV-2 back into humans is challenging, particularly in wild hosts, which are difficult to sample, and in which SARS-CoV-2 is likely to exploit complex ecologic relationships. In this study, we will assess risk of animal to human SARS-CoV-2 spillback using SEIR (Susceptible - Exposed - Infectious - Recovered) models informed by in vivo surveillance and experimental data that reflect evolving endemic SARS-CoV-2 status in humans.  These models will assess interactions between multiple animal species and humans and will be freely available for ongoing evaluation of SARS-CoV-2 spillback risk.

Coronaviral shedding in wild rodents will be assessed in partnership with the Yale Peabody Museum and CT DEEP. Samples that are positive by initial pancoronaviral RT-PCR will be sequenced to identify the specific coronavirus. SARS-CoV-2 positive or novel coronaviral samples will undergo whole genome sequencing to detect variants, recombination events with native coronaviruses, and to inform patterns of potential cross-species transmission. Sequence data will be associated with animal identity to facilitate tracking of coronaviruses and SARS-CoV-2 variants over time.

The summer internship will primarily involve rodent trapping and sampling. Rodents will be trapped in live traps (such as Sherman traps). Study sites will be selected from areas in which human food waste or other coronavirus infected wild species (e.g. white tailed deer) are accessible to rodents.  A combination of Yale-owned properties (e.g. forests or student cafeterias), city locations (New Haven, Hartford and Bridgeport) and entertainment facilities (e.g. Mohegan Sun and Foxwoods casinos) will be selected following permission by local health departments and property owners. All captured rodents will be identified to species, photographed, weighed and the sex determined. Genetic samples will be taken from each animal prior to its release at the capture site. All activity will be covered by CT DEEP permits and IACUC protocols.

Existing safety protocols and procedures will be followed at all times. All personnel are required to complete Yale Environmental Health and Safety training, (including biological safety) and to complete necessary requirements to be added to IACUC protocols. All personal protective equipment is provided.

Supervisors:          
Greg Watkins-Colwell and Kristof Zyskowski (YPM-VZ)
Caroline Zeiss (Comparative Medicine: Yale School of Medicine)

Potential Outcomes:    
This is part of a larger project (USDA-APHIS-10025-OA000000-23-0001, Zeiss, PI) submitted Jan 10, 2023.  Outcomes will be published and presented at conferences.  Results will support a regional coronaviral surveillance system and will inform public health policy.

Connection to YPM Collections:     
The VZ collections will house all field notes, photo vouchers and tissue samples (ear-punch) collected during the project. Additionally, any mammals salvaged during the project (i.e. found dead) will be prepared and cataloged at YPM. Existing mammal specimens, if determined to be suitable given collection data, will be made available to augment the study with additional samples. This internship builds a collection of rodent tissues for disease ecology and epidemiological study.  Those samples can also be used for other studies.

The intern will learn:
The intern for this project will learn field techniques related to mammal disease surveys as well as proper tissue collection methods. Additionally, the intern will have opportunity to learn specimen preparation methods for any salvaged specimens and will have opportunity to participate in some of the laboratory-based work and statistical analysis.

Restrictions on timing:     
Each of the supervisors will be away at various times during the summer 2023, but it appears that there is always at least one on campus during the 8 weeks of the project.

Length: 8 weeks

Stipend: $3,800

Collaborating Institutions:
Yale Peabody Museum (YPM)
U.S. National Museum of Natural History, Smithsonian Institution (USNM-SI)

Advisors:
Dr. Eric Sargis, Professor of Anthropology, Curator of Mammalogy, YPM
Dr. Melissa Hawkins, Curator of Mammals, USNM-SI

Description:
Undergraduates are invited to participate in museum research during the summer of 2023 (8 weeks) to work with researchers from the Yale Peabody Museum (YPM) in New Haven, CT, and the U.S. National Museum of Natural History (USNM), Smithsonian Institution in Washington, DC. This project focuses on the Nicobar Treeshrew (Tupaia nicobarica), an arboreal species that inhabits rainforests on the Nicobar Islands. This poorly studied species has different subspecies recognized from Great and Little Nicobar. Previous studies have focused on the higher-level relationships of this species based on mitochondrial DNA, but T. nicobarica has never been analyzed with a modern, integrative approach that synthesizes morphometric and molecular data. Hence, the subspecific geographic variation may represent species-level diversity that would have conservation implications for this poorly studied taxon, particularly given the impact of deforestation in much of its range. This project will build on our previous study of Southeast Asian mammals like the Common Treeshrew (Tupaia glis), a species complex in which we recognized four additional species based on our morphometric and molecular analyses. Here we will address questions such as: 1) Does T. nicobarica include multiple lineages that should be recognized as distinct species? 2) What are the relationships of T. nicobarica to other treeshrews from Southeast Asia?

The undergraduate researcher will be involved in multiple aspects of this project. At the USNM, the intern will learn how to sample museum study skins for genetic analysis (see below). At the YPM, the student will learn how to measure taxonomically informative features of skull morphology and statistically analyze the morphometric dataset. Hence, the intern will have the opportunity to learn methods of molecular and morphological data collection and analysis. This project could lead to an expanded senior thesis project, a professional presentation at the annual meeting of the American Society of Mammalogists (ASM), a peer-reviewed publication in a zoological journal, and an IUCN Red List conservation status reassessment.

Methods:
Museum specimens of Tupaia nicobarica (and their close relatives) will be sampled from either adherent muscle, cartilage, or toe pads (about 25-50 mg) for DNA extraction. All samples will be processed in a specialized clean room at the Smithsonian Institution’s Museum Support Center

designed for degraded DNA processing. DNA extraction will be performed with a commercially available kit, and library preparation will utilize a single-stranded library prep kit. After libraries are constructed, samples will be enriched for a panel of nuclear markers, as well as shotgun sequenced for mitochondrial genome sequences and pooled in equimolar ratios for sequencing on an Illumina MiSeq. Data analysis will include following established pipelines on the Smithsonian Institution’s High Performance Computing Cluster. The morphometric methods will include recording 22 measurements on each skull and analyzing these data with univariate and multivariate statistics.

Learning Objectives:
Over the course of eight weeks, the student will learn to:

• Conduct collections-based scientific research focused on the poorly studied Tupaia nicobarica;

• Measure taxonomically informative features of skull morphology;

• Learn techniques required for processing molecular data from museum specimens, including

  DNA extraction, library preparation, and in-solution enrichment;

• Statistically analyze the completed dataset; and

• Prepare an oral presentation.

Length: 8 weeks in the summer

Stipend: $5,500

Collaborative publications and presentations with previous summer interns (in bold):

Articles

2013: Sargis, EJ, Woodman, N, Reese, AT, and Olson, LE. Using hand proportions to test taxonomic boundaries within the Tupaia glis species complex (Scandentia, Tupaiidae). Journal of Mammalogy 94: 183-201. (Cover Article)

2013: Sargis, EJ, Woodman, N, Morningstar, NC, Reese, AT, and Olson, LE. Morphological distinctiveness of Javan Tupaia hypochrysa (Scandentia, Tupaiidae). Journal of Mammalogy 94: 938-947.

2014: Sargis, EJ, Woodman, N, Morningstar, NC, Reese, AT, and Olson, LE. Island history affects faunal composition: the treeshrews (Mammalia: Scandentia: Tupaiidae) from the Mentawai and Batu Islands, Indonesia. Biological Journal of the Linnean Society 111: 290-304.

2017: Sargis, EJ, Woodman, N, Morningstar, NC, Bell, TN, and Olson, LE. Skeletal variation and taxonomic boundaries among mainland and island populations of the common treeshrew (Mammalia: Scandentia: Tupaiidae). Biological Journal of the Linnean Society 120: 286-312.

2020: Woodman, N, Miller-Murthy, A, Olson, LE, and Sargis, EJ. Coming of age: morphometric variation in the hand skeletons of juvenile and adult Lesser Treeshrews (Scandentia: Tupaiidae: Tupaia minor Günther, 1876). Journal of Mammalogy 101: 1151- 1164.

2021: Juman, MM, Woodman, N, Olson, LE, and Sargis, EJ. Ecogeographic variation and taxonomic boundaries in Large Treeshrews (Scandentia, Tupaiidae: Tupaia tana Raffles, 1821) from Southeast Asia. Journal of Mammalogy 102: 1054-1066.

2021: Juman, MM, Olson, LE, and Sargis, EJ. Skeletal variation and taxonomic boundaries in the Pen-tailed Treeshrew (Scandentia, Ptilocercidae: Ptilocercus lowii Gray, 1848). Journal of Mammalian Evolution 28: 1193–1203.

2021: Woodman, N, Miller-Murthy, A, Olson, LE, and Sargis, EJ. The limitations of external measurements for aging small mammals: the cautionary example of the Lesser Treeshrew (Scandentia: Tupaiidae: Tupaia minor Günther, 1876). Journal of Mammalogy 102: 1079- 1086.

2022: Juman, MM, Millien, V, Olson, LE, and Sargis, EJ. Recent and rapid ecogeographical rule reversals in Northern Treeshrews. Scientific Reports 12: 19689.

In press: Juman, MM, Woodman, N, Miller-Murthy, A, Olson, LE, and Sargis, EJ. Taxonomic boundaries in Lesser Treeshrews (Scandentia, Tupaiidae: Tupaia minor Günther, 1876). Journal of Mammalogy.

Presentations

2011: Sargis, EJ, Woodman, N, Reese, AT, and Olson, LE. Hand proportions in treeshrews (Scandentia, Tupaiidae) and taxonomic boundaries within the Tupaia glis-belangeri species complex. Presented at the Meeting of the American Society of Mammalogists.

2013: Sargis, EJ, Woodman, N, Morningstar, NC, Reese, AT, and Olson, LE. Morphological distinctiveness of Javan Tupaia hypochrysa (Scandentia, Tupaiidae). Presented at the Meeting of the American Society of Mammalogists.

2016: Sargis, EJ, Millien, V, Woodman, N, Morningstar, NC, Bell, TN, and Olson, LE. Rule reversals: patterns of body size variation in the common treeshrew (Scandentia, Tupaiidae). Presented at the Meeting of the American Society of Mammalogists.

2019: Juman, MM, Woodman, N, Olson, LE, and Sargis, EJ. Skeletal variation among island populations of Large Treeshrews (Scandentia: Tupaiidae: Tupaia tana). Presented at the Meeting of the American Society of Mammalogists. Received the ASM Undergraduate Honoraria Award.

2021: Juman, MM, Olson, LE, and Sargis, EJ. Skeletal variation and taxonomic boundaries in the Pen-tailed Treeshrew (Scandentia, Ptilocercidae: Ptilocercus lowii Gray, 1848).

Presented at the virtual Meeting of the American Society of Mammalogists. Received the ASM Travel Award.

2022: Juman, MM, Woodman, N, Miller-Murthy, A, Olson, LE, and Sargis, EJ. Taxonomic boundaries in Lesser Treeshrews (Scandentia, Tupaiidae: Tupaia minor Günther, 1876). Presented at the Meeting of the American Society of Mammalogists. Received the ASM Travel Award.

Supervisor:
Patrick Sweeney, Collections Manager
Division of Botany
Yale University Herbarium

Project Description:
Much collection-based research revolves around describing biodiversity, an activity that is fundamental to many kinds of biological research, conservation, and other endeavors. A major focus of research within the Peabody Museum Division of Botany is on documenting and describing species-level diversity within the mangosteens.

The mangosteens (also known as the genus Garcinia) are a lineage of more than 250 species of small shrubs to medium-sized flowering trees that are a common component of lowland tropical forests throughout the world. Garcinia is probably best known for the highly prized fruit of the purple mangosteen, a tree native to southeastern Asia; however, the group exhibits several features that are of general interest to evolutionary biologists. For example, the group has exceptional floral diversity and in parts of its range, exhibits high levels of sympatric species diversity.

The research undertaken during this internship will center on better understaning species diversity within a closely related group of magnosteens endemic to Madagascar.  Presently within Madagascar, there are 32 described species of mangosteen, but recent collecting efforts and a survey of museum specimens suggests that there could be many undescribed species. As part of this internship an interested student would gather morphological, distributional, and ecological data and then analyse these data to determine whether they support the existence of undescribed species of Garcinia in Madagascar.

The Yale University Herbarium is a dynamic collection housing over 360,000 specimens of vascular plants, algae, mosses, fungi, and lichens from throughout the world. Researchers utilize these specimens for a variety of purposes, from documenting the occurrence of rare and endangered species to serving as source of genetic material for evolutionary studies.

Internship length: 6 weeks

Stipend: $2,850

I may be away at a conference during July 22 – 26; however, the student may be able to work independently while I am away.

Description:
Night lizard evolution is particularly emblematic of the deep-time history of North America.  But few would ever know it, as they are so secretive, living their long, low-energy-consuming lives while hidden in confined spaces beneath logs and other plant trash or rocks covering the ground.  They were rare members of Cretaceous ecosystems but became abundant and diverse following the asteroid impact 66 million years ago that wiped out nearly all the dinosaurs.  Although more than 85% of lizard species also disappeared at this time, Night lizard ecology left them perfectly positioned both to survive the consequences of the asteroid impact and to exploit this devastated ecosystem as it rebounded from mass extinction.  Night lizards are fundamentally ‘tropical’ lizards adapted to the Hot House climates widespread during this era.  Following the fall into Ice House climates, ecosystems became colder and drier at middle latitudes and forests gave way to grasslands.  Night lizards preferring warmer and wetter conditions became restricted to lower latitudes.  Those that remained at middle latitudes had to adapt to radically different conditions in which there were many fewer log-producing plants, especially in more arid regions.  Fortunately for Night lizards, arid-land agaves and yuccas radiated at this time, producing at least some suitable habitat.  Because these plants tend to be more dispersed, restricted in areal extent, and much smaller than ‘trees’ at lower latitudes, Night lizards shrank markedly in body size to take advantage of these more restricted dwellings.

Currently, all Night lizards in North America prior to about 25 million years ago are commonly referred to as species of Palaeoxantusia, and thereafter to species of Xantusia.  Unfortunately, although the latter group may be real, the former is certainly not, as it includes species belonging to very different groups of Night lizards.  Before this conundrum can be sorted out, we first need to discover how many species are represented in their fossil record.

Tooth-bearing bones are the densest parts of the lizard skeleton and accordingly comprise >90% of the lizard fossil record.  To make matters worse, these jaw bones are often broken and incomplete.  Luckily, the back end of the lower jaw preserves enough anatomy to help tell them apart and place them in a general way in the Night lizard Tree of Life.  That said, they are quite small and very similar in overall shape, so the differences among them should be quantified.  To that end, I have had many of these fossils CT-scanned by YPM’s skilled fossil preparator Marilyn Fox. 

I’m looking for someone who’d like to learn how to make 3D digital images of these fossils and perform elementary geometric morphometrics on them.  Using computers and software in my lab, the successful intern will reassemble individual CT slices into complete digital images of the fossils, and then take ~ 12 measurements on each of them. 

Earth and Planetary Sciences Professor Jacques Gauthier will familiarize the intern with Night lizard evolution and anatomy and identify the particular points on the jaws that will root the morphometric analyses.  Bio-Anthropology Graduate student Spencer Irvine will show the intern how to use morphometric software to take measurements and analyze them statistically (all built into the software).  Although the image-generating system and geometric morphometric package both have a bit of a learning curve, these packages that are pretty easy to master.
I hope that the intern will participate in the description and naming of the several new species that will be published emerge from this study.

Length: 8 weeks

Stipend: $3,800