Featured Research

from universities, journals, and other organizations

Study Rules Out Inbreeding As Cause Of Amphibian Deformities

Date:
November 3, 2008
Source:
Purdue University
Summary:
Although research has linked inbreeding with elevated rates of deformity in a wide variety of animals, a new study finds it plays no part in the high incidence of malformation among salamanders.

A Purdue study found deformities in 8 percent of the 2,000 tiger salamanders examined, like this five-legged individual photographed in April 2004. Purdue researcher Rod Williams has ruled out inbreeding, which has been linked with elevated rates of deformity in a wide variety of animals, as a cause.
Credit: Purdue University Forestry and Natural Resources

Although research has linked inbreeding with elevated rates of deformity in a wide variety of animals, a new study finds it plays no part in the high incidence of malformation among salamanders.

Related Articles


Purdue University researchers recently examined 2,000 adult and juvenile salamanders and found that 8 percent had visible deformities, mainly consisting of missing, extra or dwarfed digits (equivalent to fingers and toes). That is double the rate of malformation found in newts, a related amphibian, but on par and with frequencies seen in many frog species, said assistant professor of forestry and natural resources Rod Williams.

"This is really the first study to test - and disprove - the hypothesis that inbreeding is responsible for malformations in salamanders," said Williams, corresponding author of the study published recently in the journal Biology Letters.

Like many types of amphibians, tiger salamanders return to the same pond throughout their lives to mate. Williams and his former doctoral adviser, lead author Andrew DeWoody, hypothesized that habitat fragmentation or other factors might increase the probability that related salamanders could return to the same spot and mate.

But their study found animals' genetic backgrounds to be unrelated to deformation rates; deformed salamanders were no more inbred than normal individuals. The population proved to be quite diverse, in fact, with roughly twice as much genetic variation as most land animals, DeWoody said.

They calculated relatedness by measuring frequencies of alleles, which are copies or pairs of genes whose ratios are abnormally skewed in inbred individuals.

High rates of amphibian malformation concern scientists not only because they threaten the survival of certain important species, but also because of what they signify about the health of the environment, said DeWoody, an associate professor.

"Amphibians are a good bio-indicator species - real canaries in the coal mine," Williams said.

Amphibians are more heavily impacted by water pollutants because of their semipermeable skin. Many species also begin life in water, where they risk contaminant exposure during their most vulnerable years, Williams said.

The reason for high rates of deformation in salamanders, frogs and other amphibians remains a mystery, DeWoody said. With inbreeding ruled out, however, environmental factors like parasites, ultraviolet radiation and water pollution remain prime suspects, he said.

Williams and DeWoody are actively looking for a cause or causes that may shed light upon high levels of malformation in frogs and other amphibians.

"We've crossed out inbreeding as a possibility, an important step forward," DeWoody said. "But there's a lot of work yet to do."


Story Source:

The above story is based on materials provided by Purdue University. Note: Materials may be edited for content and length.


Cite This Page:

Purdue University. "Study Rules Out Inbreeding As Cause Of Amphibian Deformities." ScienceDaily. ScienceDaily, 3 November 2008. <www.sciencedaily.com/releases/2008/10/081028184746.htm>.
Purdue University. (2008, November 3). Study Rules Out Inbreeding As Cause Of Amphibian Deformities. ScienceDaily. Retrieved April 18, 2015 from www.sciencedaily.com/releases/2008/10/081028184746.htm
Purdue University. "Study Rules Out Inbreeding As Cause Of Amphibian Deformities." ScienceDaily. www.sciencedaily.com/releases/2008/10/081028184746.htm (accessed April 18, 2015).

Share This


More From ScienceDaily



More Plants & Animals News

Saturday, April 18, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Un-Bee-Lievable: Bees on the Loose After Washington Truck Crash

Un-Bee-Lievable: Bees on the Loose After Washington Truck Crash

Reuters - US Online Video (Apr. 17, 2015) A truck carrying honey bees overturns near Lynnwood, Washington, spreading boxes of live bees across the highway. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Our Love Of Puppy Dog Eyes Explained By Science

Our Love Of Puppy Dog Eyes Explained By Science

Newsy (Apr. 17, 2015) Researchers found a spike in oxytocin occurs in both humans and dogs when they gaze into each other&apos;s eyes. Video provided by Newsy
Powered by NewsLook.com
Dog Flu Spreading in Midwestern States

Dog Flu Spreading in Midwestern States

AP (Apr. 17, 2015) Dog flu is spreading in several Midwestern states. Dog daycare centers and veterinary offices are taking precautions. (April 17) Video provided by AP
Powered by NewsLook.com
Raw: Rare Whale Spotted in Gulf of Mexico

Raw: Rare Whale Spotted in Gulf of Mexico

AP (Apr. 17, 2015) Researchers from the E/V Nautilus had quite a surprise Tuesday, when a curious sperm whale swam around their remotely operated vehicle in the Gulf of Mexico. Cameras captured the encounter. (April 17) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Plants & Animals

Earth & Climate

Fossils & Ruins

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins