Current Projects in
In recent years we've collaborated with Holly Rushmeier (Dept. of Computer Science, Yale University) to develope 3D methods to reconstruct the form of organisms in field conditions. We are using this method for 3D reconstruction of the carapace of Giant Galapagos tortoises for morphometric analyses.
These projects are in collaboration with Jeffrey Powell. Current lab members involved in the project are Chaz Hyseni, and Scott Glaberman plus a large international team of scientists, including past-postdoctoral associates and graduate students, and scientists from the Galapagos National Park and the Charles Darwin Research Station (Galapagos, Ecuador). Past lab members involved, or still a part of the research team are: Luciano Beheregaray, Claudio Ciofi, Ylenia Chiari, Valerio Ketmeier, Gabriele Gentile, Michel Milinkovitch, Nikos Poulakakis, and Michael Russello. This project benefited by the collaboration of several EEB graduate students and undergraduates, which have co-authored many of the publications.
We have developed molecular markers for nuclear and mtDNA region for this species and almost completed the genetic screen of 600+ samples collected in our 2004 field season. In multiple populations we have compared the genetic make-up of samples before and after a severe oil-spill in 2001 and before and after a severe El Nino event (19) to evaluate the impact of environmental or human induced stress (>60% mortality in the populations affected by the spill; 90% mortality rates for some populations after the 1985 El nino year) on patterns and levels of genetic diversity. In parallel to the development of neutral DNA markers we are also engaged in developing non-neutral markers associated with the Major Histocompatability Loci (MHC). These genes are traditionally associated with the capacity of organisms to respond to environmental changes or stress. We are also completing a detailed metapopulation study of the iguanas from the island of Santa Fe to obtain baseline data for paternity and demographic studies to associate with ongoing behavioral work on this population carried out by Dr. Martin Wikelski and his lab at the Max Planck Institute, Germany.
Scott Glaberman is the current member of the lab involved in this work. Past lab members involved with the project are Sebastian Steinfartz and Deborah Lantenbecq (University of Mons-Hainaut, Belgium).
Aldabra Giant tortoises
For the past few years we have been involved with several research projects aimed at understanding the evolutionary relationships of tortoises from the Indian Ocean, including extant and extinct species. Our work has focused on endangered Madagascar tortoises and on the Giant Aldabra tortoise.
Past lab members involved with the project are: Claudio Ciofi (Un. of Florence, Italy), Oliver Balmer and Eric Palkovacs.
The Amur Tiger, Panthera tigris altaica, is a rare subspecies of tiger. Also known as the Siberian, Korean, Manchurian, or North China Tiger, and is critically endangered. An initial survey of mtDNA levels of genetic diversity in the only wild population of this species was conducted by Michael Russello. This was followed by a a screen of microsatellite variation and the development of a molecular test to identify sex from scats. We have also screened for variation in the captive population, since our preliminary results suggest that this population harbors more genetic variation than the wild one. Additional collaborators for this project include: Dale Miquelle (WCS Russia program), Philippe Henry, Kathy Traylor-Holzer (AZA Tiger Regional Studbook Keeper) and several Yale undergraduates.
Phylogeography of the Greater Prairie Chicken (Tympanuchus cupido) Including the Extinct Heath Hen: Potential Implications for Conservation and Management
Discovering the importance of genetic structuring within and among populations of a species is extremely important for understanding population biology and evolution. The degree of genetic differentiation between populations and the role of subspecies in taxonomy have gained heightened attention due to our current conservation paradigm which relies heavily on subspecific distinctions for granting protection. In this project we explored the phylogenetic relationships among subspecies and populations of the greater prairie chicken (Tympanucus cupido.). The greater prairie chicken complex represents three subspecies, two extant and one extinct. The most widespread subspecies is the greater prairie chicken (T. cupido pinnatus) of the Midwestern U.S. The Attwater’s prairie chicken (T. cupido attwateri), formerly of the Gulf Coast, is now highly endangered and restricted to a small isolated population in Texas. The heath hen (T. cupido cupido), formerly of the Northeastern U.S., was extirpated from mainland North America by around 1870, with a remnant population persisting on the island of Martha’s Vineyard, Massachusetts until its final extinction in 1932. We elucidated levels and patterns of genetic differentiation within and among subspecies and populations of greater prairie chickens based on mtDNA sequence analysis. The results of this research provide answers to important evolutionary questions but are useful in addressing conservation and management issues.
Past lab members involved with the project are: Eric Palkovacs.