WT Professor Part of Major Study on Tortoise DNA Published in Science Magazine

Photo: A Mojave desert tortoise is seen in the U.S. Fish and Wildlife Service's Large Scale Translocation Site in the Ivanpah Valley southeast of Las Vegas. Photo by Roy C. Averill-Murray

Copy by Chip Chandler, 806-651-2124, cchandler@wtamu.edu

CANYON, Texas — A recently published major research project by a West Texas A&M University assistant professor is a reminder to go where the science leads.

Dr. Peter A. Scott is the lead author of a study of the DNA of Mojave desert tortoises that appeared as the cover story of the Nov. 27 issue of Science.

“It’s pretty wild,” said Scott, an assistant professor of wildlife biology. “It’s not something I ever thought studying some tortoise DNA would get me. Part of that is that these results stem from a side project, so one of the main lessons is to listen to what the data says and be flexible enough to go where it tells you. Sometimes, you get an unexpected but powerful result.”

Scott and his fellow researcher at UCLA, where he did postdoctoral studies, collaborated with the U.S. Fish and Wildlife Service to study the DNA of desert tortoises that had been placed in its Large Scale Translocation Site in the Ivanpah Valley southeast of Las Vegas.

Many of the tortoises were kept as pets, which became illegal when the animals were added to the endangered species list, or had to be moved because of development. The agency actively ran the site from 1997 to 2014 and officials there wanted to see if the fence around the site could be removed, allowing the tortoises to reenter the wild without causing negative consequences.

“Releasing a bunch of genes into the environment that don’t belong there could potentially harm neighboring populations of animals,” Scott said.

According to UCLA, the agency took blood samples and marked each animal before releasing them into the site, making it possible to track the animals. The UCLA researchers sequenced the DNA of 166 tortoises, both alive and dead, and initially were looking to see if the tortoises’ places of origin correlated to their chances of survival.

What Scott and his team found, though, was that tortoises with more genetic variation, or heterozygosity, survived at higher rates than those without.

“We didn’t know what we were going to find,” Scott said. “Honestly, we thought either their population of origin or the distance from which they came would be a stronger indicator of survival rates, but those measures all came out even, so we had to look for something else to study.”

Most organisms, Scott said, have two copies of every part of their genetic makeup — one from the mother, one from the father. Heterozygosity is a measure of how different those two copies are. In this case, the tortoises had a stronger chance of surviving when they had more variation in their genomes.

“It flies in the face of what we know from other translocation studies, but lots of genetic variation was hands-down the best predictor of whether a tortoise lived or died,” said Brad Shaffer, a professor of ecology and evolutionary biology and director of the UCLA La Kretz Center for California Conservation Science, in a UCLA news release. “Relocating endangered plants and animals is increasingly necessary to counteract the effects of climate change, and this gives us a new tool to increase survival rates.”

In addition to helping solve a scientific conundrum, Scott said he hopes this study will have an impact on his students at WT, where he began teaching in August.

“My goal overall is that this allows students to see that this sort of work is accessible for them to do as well,” Scott said. “I hope they take the lesson of not starting a project with a preconceived goal but rather let the data show them what the answers are.”

“Few scientists have work worthy of publication in Science,” said Dr. Kevin Pond, dean of the Paul Engler College of Agriculture and Natural Sciences. “We are extraordinarily proud of Dr. Scott’s accomplishments and that he completed this project while teaching at WT.”

Attracting faculty members such as Scott is part of WT’s goal of becoming a regional research university, as laid out in the University’s long-term plan, WT 125: From the Panhandle to the World.

About West Texas A&M University

WT is located in Canyon, Texas, on a 342-acre residential campus. Established in 1910, the University has been part of The Texas A&M University System since 1990. With enrollment of more than 10,000, WT offers 60 undergraduate degree programs, 38 master’s degrees and two doctoral degrees. The University is also home to the Panhandle-Plains Historical Museum, the largest history museum in the state and the home of one of the Southwest’s finest art collections. The Buffaloes are a member of the NCAA Division II Lone Star Conference and offers 15 men’s and women’s athletics programs.

—WTAMU—