Frogs' bright colors cue scientists to diversity

Aug 22, 2012 By Fran Simon
Frogs' bright colors cue scientists to diversity
Tulane students are studying evolutionary changes of poison dart frogs, such as this blue morph of the strawberry poison frog from the Aguacate peninsula of Panama. Photo by Deyvis Gonzalez

Tiny poison dart frogs living wild in Panama may provide clues about relatively rapid biodiversification, says Tulane University evolutionary biologist Corinne “Cori” Richards-Zawacki. Her team of students has spent most of the summer at two field sites on an archipelago studying natural selection.

“I work out most of the logistics, and then I bow out,” letting the students gain experience as researchers, says Richards-Zawacki, an assistant professor of ecology and evolutionary biology.

Aposematism — the combination of toxicity and bright coloration — is the major defense mechanism of the poison dart . In , these frogs have skin with a variety of colors: blue, green, red, orange, white and spotted.

“Their coloration is an advertisement of sorts, saying ‘do not attempt to eat!’” says Richards-Zawacki.

Frogs' bright colors cue scientists to diversity
Tulane students are studying evolutionary changes of poison dart frogs, such as this blue morph of the strawberry poison frog from the Aguacate peninsula of Panama. Photo by Deyvis Gonzalez

In one experiment, the students observe the behavior of chicks upon spotting the vividly hued frogs. The ’ observations will answer questions about how predators hunt frogs based on coloration.

“The chicks pick up the frogs in their beaks, but the frogs taste bad so they spit them out right away,” says Richards-Zawacki. “Do the chicks avoid all of the colors — green and blue, as well as red? Or just the color that they’ve learned to avoid?”

Neither the nor frogs are harmed by the taste-testing, she says.

The team also is looking at how barriers to reproduction may influence diversification.

“Understanding how we got the diversity of life here on Earth is important for conservation,” Richards-Zawacki says. “If we want to conserve a species, we also need to conserve its ability to adapt and undergo natural evolutionary processes.”

Explore further: Deep sea fish eyesight similar to human vision

More information: An August issue of Molecular Ecology features a paper by Richards-Zawacki, “Mate choice and the genetic basis for colour variation in a polymorphic dart frog: inferences from a wild pedigree,” with one of the team’s photos on the cover.

Related Stories

Scientists use frogs to battle superbugs

Mar 19, 2012

(PhysOrg.com) -- Nuclear scientists using frogs in a battle against superbugs might sound like some kind of 1980s computer game – but it’s actually scientific research underway right now.

New tool enhances view of muscles

Jan 23, 2012

Simon Fraser University associate professor James Wakeling is adding to the arsenal of increasingly sophisticated medical imaging tools with a new signal-processing method for viewing muscle activation details that have never ...

Unraveling malaria's genetic mysteries

Dec 22, 2011

(PhysOrg.com) -- Simon Fraser University researchers in biology and computing sciences are starting to piece together a picture that may help scientists and doctors save more than a million lives annually.

Recommended for you

Dogs hear our words and how we say them

Nov 26, 2014

When people hear another person talking to them, they respond not only to what is being said—those consonants and vowels strung together into words and sentences—but also to other features of that speech—the ...

Amazonian shrimps: An underwater world still unknown

Nov 26, 2014

A study reveals how little we know about the Amazonian diversity. Aiming to resolve a scientific debate about the validity of two species of freshwater shrimp described in the first half of the last century, ...

Factors that drive sexual traits

Nov 26, 2014

Many male animals have multiple displays and behaviours to attract females; and often the larger or greater the better.

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.