Navigation Links
Females can place limits on evolution of attractive features in males, research shows
Date:8/4/2011

AUDIO: Male tngara frogs producing their distinctive "whine " and "chuck " calls to attract females.

Click here for more information.

AUSTIN, TexasFemale cognitive ability can limit how melodious or handsome males become over evolutionary time, biologists from The University of Texas at Austin, Louisiana State University Health Sciences Center and the Smithsonian Tropical Research Institute have observed.

Males across the animal world have evolved elaborate traits to attract females, from huge peacock tails to complex bird songs and frog calls. But what keeps them from getting more colorful feathers, longer tails, or more melodious songs? Predators, for one. Increased elaboration can draw predators in, placing an enormous cost to males with these sexy traits.

In a new paper appearing this week in Science, a group of biologists have shown that females themselves can also limit the evolution of increased elaboration.

Studying neotropical tngara frogs, they found that females lose their ability to detect differences in male mating calls as the calls become more elaborate.

"We have shown that the female tngara frog brains have evolved to process some kinds of information and not others," says Mike Ryan, professor of integrative biology at The University of Texas at Austin, "and that this limits the evolution of those signals."

Imagine looking at a group of five oranges next to a group of six. At a glance, you would quickly notice that one group has one more orange than the other. Now, imagine looking at a pile of 100 oranges next to a pile of 101. It would be nearly impossible for you to notice the difference in size (one orange) between those two piles at a glance. This is known as Weber's Law, which states that stimuli are compared based on proportional differences rather than absolute differences (one orange in the case above).

In tngara frogs, males gather en masse to attract female frogs with a call that is made up of a longer "whine" followed by one or more short "chucks."

Through a series of experiments conducted in Panama, Ryan and his collaborators found that females prefer male calls with the most chucks, but their preference was based on the ratio of the number of chucks. As males elaborate their call by adding more chucks, their relative increase in attractiveness decreases due to a perceptual constraint on the part of females.

Male tngara frog calls also attract a predator: the frog eating fringe-lipped bat. To confirm that male song elaboration wasn't limited by these predators, the researchers also studied how the bats respond to additional "chucks" in the male call.

They discovered that hunting bats choose their prey based on chuck number ratio, just as the female frogs do. So, as males elaborate their call by adding chucks, the relative increase in predation risk decreases with each additional chuck.

"What this tells us is that predation risk is unlikely to limit male call evolution," says Karin Akre, lecturer at The University of Texas at Austin. "Instead, it is the females' cognition that limits the evolution of increasing chuck number."


'/>"/>

Contact: Karin Akre
kakre@mail.utexas.edu
512-475-6164
University of Texas at Austin
Source:Eurekalert  

Related biology news :

1. Avian Axe effect attracts attention of females and males
2. Competition between females leads to infanticide in some primates
3. In fireflies, flightless females lose out on gifts from males
4. Differences in brain development between males and females may hold clues to mental health disorders
5. Male antelopes trick females into extra sex opportunities
6. Male antelopes deceive females to increase their chances of mating
7. Females shut down male-male sperm competition in leafcutter ants
8. Pesticide atrazine can turn male frogs into females
9. Exposure to young triggers new neuron creation in females exhibiting maternal behavior
10. Pesky fruit flies learn from experienced females: Study
11. Caffeine appears to be beneficial in males -- but not females -- with Lou Gehrigs disease
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Females can place limits on evolution of attractive features in males, research shows
(Date:6/21/2016)... 21, 2016 NuData Security announced today that ... of principal product architect and that Jon ... customer development. Both will report directly to ... moves reflect NuData,s strategic growth in its product ... customer demand and customer focus values. ...
(Date:6/9/2016)... June 9, 2016 Paris ... Teleste,s video security solution to ensure the safety of people ... during the major tournament Teleste, an international ... and services, announced today that its video security solution will ... to back up public safety across the country. The system ...
(Date:6/2/2016)... Perimeter Surveillance & Detection Systems, ... Infrastructure, Support & Other Service  The latest ... comprehensive analysis of the global Border Security market ... of $17.98 billion in 2016. Now: In ... in software and hardware technologies for advanced video surveillance. ...
Breaking Biology News(10 mins):
(Date:6/23/2016)... , ... June 23, 2016 , ... ... release of its second eBook, “Clinical Trials Patient Recruitment and Retention Tips.” Partnering ... retention in this eBook by providing practical tips, tools, and strategies for clinical ...
(Date:6/23/2016)... , June 23, 2016 A person commits ... the crime scene to track the criminal down. ... U.S. Food and Drug Administration (FDA) uses DNA evidence to ... Sound far-fetched? It,s not. The FDA has ... to support investigations of foodborne illnesses. Put as simply as ...
(Date:6/23/2016)... , June, 23, 2016  The Biodesign Challenge ... envision new ways to harness living systems and biotechnology, ... Art (MoMA) in New York City ... 130 participating students, showcased projects at MoMA,s Celeste Bartos ... Paola Antonelli , MoMA,s senior curator of architecture and ...
(Date:6/23/2016)... Durham, NC (PRWEB) , ... June 23, 2016 , ... ... Odense University Hospital in Denmark detail how a patient who developed lymphedema after being ... (fat) tissue. The results could change the paradigm for dealing with this debilitating, frequent ...
Breaking Biology Technology: