Why Isn't Ctenomys sociabilis Extinct? Lessons from an Endemic Species About Response to Climatic ChangeEPA Grant Number: FP916401
Title: Why Isn't Ctenomys sociabilis Extinct? Lessons from an Endemic Species About Response to Climatic Change
Investigators: Chan, Yvonne L.H.
Institution: Stanford University
EPA Project Officer: Cobbs-Green, Gladys M.
Project Period: January 1, 2004 through December 31, 2006
Project Amount: $111,344
RFA: STAR Graduate Fellowships (2004) RFA Text | Recipients Lists
Research Category: Fellowship - Zoology , Academic Fellowships , Biology/Life Sciences
The objective of this research project is to understand the response of animal populations to climatic change, which is essential for the future maintenance of biodiversity. One question that remains difficult to answer and is particularly important to conservation, is how animals respond over time scales relevant to evolutionary change.
Ancient DNA provides a unique opportunity to track animal response to Holocene climate change and to study species-replacement patterns and genetic diversity over time. We used ancient DNA to compare response to climatic change in two species, Ctenomys sociabilis and Ctenomys haigi, over the last 8,000 years. Our study site, Cueva Traful, is a late-Holocene raptor roost in Parque Naiconal Nahuel Huapi, Argentina. A lack of genetic diversity in modern C. sociabilis populations is indicative of past bottleneck events. A previous ancient DNA study found that it had remained genetically identical for at least 1,000 years in the face of climatic change and human disturbance. Because Cueva Traful goes back further in time, our first goal was to examine genetic diversity to place a longer historical perspective on the modern bottleneck. The second goal was to compare changes in genetic diversity in C. sociabilis to C. haigi, a closely related species that may respond differently to climatic change. The use of ancient DNA presents unique challenges as a result of low copy number, environmental damage to template, and high contamination risk. Despite these challenges, ancient DNA provides a unique perspective on evolutionary history.