Breathing life into an extinct species: Ancient DNA cracks the case

Jun 15, 2011
Breathing life into an extinct species: Ancient DNA cracks the case
Created by Peter Maas for The Extinction Website. This image has been released under the Creative Commons Attribution Non-commercial No Derivatives 3.0 Licence.

The Vegas Valley Leopard Frog is the only North American frog officially considered to have gone extinct in recent history (c. 1942). But through the efforts of a multi-agency genetic investigation comprised of dedicated researchers from the Las Vegas Springs Preserve, Fordham University, University of Nevada Las Vegas, University of Arizona, Arizona Game and Fish Department, the U.S. Environmental Protection Agency, and Tulane University it has been discovered that the frog is not extinct, but genetically identical to a species located 250 miles away from Las Vegas.

“There are several species of leopard frogs in the southwest and, even though they are not the same species, they all look quite similar even to herpetologists—biologists who study amphibians and reptiles,” said Dr. Raymond Saumure, Springs Preserve Biologist, who initiated the study. Dr. Saumure became interested in the frog because the Las Vegas Springs Preserve was one of three spring systems once inhabited by the species.  

“What we initially set out to do,” said Dr. Saumure “was to determine if the Vegas Valley Leopard Frog (Rana fisheri) was the same species as the imperiled Relict Leopard Frog (Rana onca) found along tributaries of the Colorado River, several miles to the east.”  

To answer that question, Dr. Evon Hekkala, then a post-doc at Tulane University, was enlisted to conduct the genetic analyses. To make the study possible, useable DNA had to be extracted from Vegas Valley Leopard Frogs collected in Las Vegas in 1913 and housed at the California Academy of Sciences.

“Our first success was to extract useable strands of DNA from these frogs preserved almost 100 years ago” says Dr. Hekkala, now an Assistant Professor at Fordham University.  

The initial results were discouraging, despite their physical similarities and geographic proximity, the frogs were not the same species. The question remained whether the Vegas Valley Leopard Frog was truly extinct.

With the DNA extracted, Dr. Hekkala was able to compare it to data in GenBank, a database that contains DNA sequence data for a myriad of organisms, including 62 other species of frogs from North America.

What the research team found, as published in the scientific journal “Conservation Genetics”, was that the Vegas Valley Leopard Frog was virtually identical, genetically speaking, to the Threatened Chiricahua Leopard Frog (Rana chiricahuensis), a species whose DNA was being studied independently by the Arizona co-authors.

“It meant” says Dr. Hekkala “that the only North American frog currently listed as extinct was not extinct!”  

For a team of conservation-minded biologists, it meant that they’d been given a second chance. Today, the closest Chiricahua Leopard Frog population, direct relatives of the Vegas Valley Leopard is in the Mogollon Rim in central Arizona, some 250 miles to the southeast of Las Vegas.

Explore further: Clues to aging from long-lived lemurs

More information: Click here to access published article.

Related Stories

Laos said to harbor many new frog species

Apr 20, 2006

The Wildlife Conservation Society in New York says new species of frogs -- and lots of them -- are being discovered in the Southeast Asia nation of Laos.

Unique frog helps amphibian conservation efforts

Mar 07, 2011

A tropical frog – the only one of its kind in the world – is providing conservationists with exclusive insights into the genetic make-up of its closest endangered relatives.

New golden frog discovered in remote region of Colombia

Aug 28, 2007

A new poisonous frog was recently discovered in a remote mountainous region in Colombia by a team of young scientists supported by the Conservation Leadership Programme (CLP). The new frog, which is almost two centimetres ...

Recommended for you

Clues to aging from long-lived lemurs

15 hours ago

When Jonas the lemur died in January, just five months short of his thirtieth birthday, he was the oldest of his kind. A primate called a fat-tailed dwarf lemur, Jonas belonged to a long-lived clan. Dwarf ...

Cats relax to the sound of music

20 hours ago

According to research published today in the Journal of Feline Medicine and Surgery by veterinary clinicians at the University of Lisbon and a clinic in the nearby town of Barreiro in Portugal, music is likew ...

Fruit flies crucial to basic research

21 hours ago

The world around us is full of amazing creatures. My favorite is an animal the size of a pinhead, that can fly and land on the ceiling, that stages an elaborate (if not beautiful) courtship ritual, that can ...

Crete's mystery croc killed by cold snap

21 hours ago

A man-eating crocodile that became an attraction on the Greek island of Crete last year after its mysterious appearance in a lake has died, probably of cold, an official said Monday.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.