Green poison-dart frog varies mating call to suit situation

Nov 11, 2013
This is a green poison-dart frog. Credit: Beatriz Willink

In the eyes of a female poison-dart frog, a red male isn't much brighter than a green one. This does not however mean that the mating behavior of the green and red variants of the same species of frog is exactly the same. A study in Springer's journal Behavioral Ecology and Sociobiology, led by Beatriz Willink of the Universidad de Costa Rica in Costa Rica, sheds light on these findings.

The bright colors of poison-dart frogs serve not only to attract potential mates, but also to warn possible predators such as birds that these amphibians are poisonous. Different color variants within the same species occur, such as in the granular poison frog (Oophaga granulifera) of the southwestern lowlands of Costa Rica, where yellow and green color morphs have evolved from red ancestors.

Willink and her colleagues wanted to test if the green variants of the granular poison frog were more or less conspicuous to potential mates and predators than red ones of the same species. Therefore, they measured how the skin of the frogs contrasted with their natural background. This was done because dorsal brightness is known to influence female preferences in at least one poison frog species. The calling activity of 12 red and 10 green male frogs was also noted to determine if green males adjust their display behavior according to the availability of potential mates.

The results show that the green frogs, despite being less visible in some cases, may appear as bright as red frogs to members of their own species - but not to birds - when they are viewed on dark backgrounds.

This is a red poison-dart frog. Credit: Beatriz Willink

Green therefore seem to adjust their sexual behavior accordingly: They can deliver relatively conspicuous signals to females while being less conspicuous to potential . The researchers found that green males called less frequently than red males when advertising to distant females. However, their calling activity dramatically increased when a female was near and they became as vocal as red males. In the right context, when mating opportunity is certain, green males appear to trade-off the risk of predation for the mate-securing benefits of bold behavior.

"Our results support the notion that populations of phenotypically or observably different divergent species may use different solutions to the trade-off between natural and sexual selection, by adjusting the place and time of displays to risks and opportunities," says Willink. "In this may have contributed to the dramatic variation in color pattern conspicuousness observed across ."

Explore further: Lovelorn frogs bag closest crooner

More information: Willink, B. et al (2013). Conspicuous displays in cryptic males of a polytypic poison-dart frog, Behavioral Ecology and Sociobiology. DOI: 10.1007/s00265-013-1640-4

Related Stories

Lovelorn frogs bag closest crooner

May 20, 2013

What lures a lady frog to her lover? Good looks, the sound of his voice, the size of his pad or none of the above? After weighing up their options, female strawberry poison frogs (Oophaga pumilio) bag th ...

Frogs' bright colors cue scientists to diversity

Aug 22, 2012

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 ...

Vision stimulates courtship calls in the grey tree frog

Nov 19, 2012

Male tree frogs like to 'see what they're getting' when they select females for mating, according to a new study by Dr. Michael Reichert from the University of Wisconsin-Milwaukee in the US. His work, which is one of the ...

Croaking chorus of Cuban frogs make noisy new neighbors

May 31, 2013

Human-produced noises from sources such as traffic and trains can substantially impact animals, affecting their ability to communicate, hunt, or even survive. But can the noise made by another animal have the same detrimental ...

Frogs use calls to find mates with matching chromosomes

Dec 27, 2011

When it comes to love songs, female tree frogs are pretty picky. According to a new study from the University of Missouri, certain female tree frogs may be remarkably attuned to the songs of mates who share the same number ...

Recommended for you

Orchid named after UC Riverside researcher

17 hours ago

One day about eight years ago, Katia Silvera, a postdoctoral scholar at the University of California, Riverside, and her father were on a field trip in a mountainous area in central Panama when they stumbled ...

In sex-reversed cave insects, females have the penises

19 hours ago

Researchers reporting in the Cell Press journal Current Biology on April 17 have discovered little-known cave insects with rather novel sex lives. The Brazilian insects, which represent four distinct but re ...

Fear of the cuckoo mafia

19 hours ago

If a restaurant owner fails to pay the protection money demanded of him, he can expect his premises to be trashed. Warnings like these are seldom required, however, as fear of the consequences is enough to ...

User comments : 0

More news stories

Male monkey filmed caring for dying mate (w/ Video)

(Phys.org) —The incident was captured by Dr Bruna Bezerra and colleagues in the Atlantic Forest in the Northeast of Brazil.  Dr Bezerra is a Research Associate at the University of Bristol and a Professor ...

Scientists tether lionfish to Cayman reefs

Research done by U.S. scientists in the Cayman Islands suggests that native predators can be trained to gobble up invasive lionfish that colonize regional reefs and voraciously prey on juvenile marine creatures.

Leeches help save woman's ear after pit bull mauling

(HealthDay)—A pit bull attack in July 2013 left a 19-year-old woman with her left ear ripped from her head, leaving an open wound. After preserving the ear, the surgical team started with a reconnection ...