Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Scientists find male finches frugal in their attempts to attract females

03.02.2005


Attracting a mate can be a costly endeavor, according to a University of North Carolina at Chapel Hill scientist, but new experiments he helped lead show that some male animals economize on courting when the chance of success seems low.
Dr. Keith W. Sockman, assistant professor of biology in UNC’s College of Arts and Sciences, studies mating behavior in songbirds and the songs that play such a central role in their reproduction. "From people to praying mantises, individuals invest everything from their homes to their heads to attract a member of the opposite sex," Sockman said. "When male songbirds sing to attract a mate, they expend energy during times they could otherwise be foraging for seeds and grubs.

"They may also increase their exposure to predators," the biologist said. "This led us to predict that when females are in short supply or infertile, unmated males should reduce these ’costs’ by singing less."


In a paper published in the new issue of the journal Biology Letters, Sockman and colleagues Dr. Thomas P. Hahn and Kendra B. Sewall of the University of California at Davis and Dr. Gregory F. Ball of Johns Hopkins University in Baltimore, report that male songbirds are frugal in their efforts to attract a mate.

Studying Cassin’s finches, which breed in the Sierra Nevada Mountains of California, the scientists found that males sang the most in response to the loss of a prospective mate but sang very little either in the presence of a mate or when females were unlikely to be nearby.

The researchers concluded that male Cassin’s finches adjust their mate-attraction efforts according to their need for a mate and the likelihood of attracting one. "But the story gets better," Sockman said. "After the breeding period was over, we determined the relative fertility of females by measuring when each began feather molt."

Because molt begins when fertility ends, the scientists could infer when each female had been at the peak of her fertility during the experiment when males were exposed to them. "To our great surprise, we discovered that males somehow ascertain female fertility and sing the most when trying to attract the most fertile females," Sockman said. "Thus, males temper their efforts in attracting a mate depending on the likelihood of a payoff."

Dr. Mark E. Hauber is a behavioral ecologist at the University of Auckland in New Zealand and an expert in bird behavior. "Since Darwin’s writings, we have assumed that females are the choosy sex, but apparently males are being choosy in their own way," Hauber said. "They simply don’t put in the effort for less fertile females.

"Economic decisions of this sort are likely adaptive because males would not incur large costs on investments yielding low returns," he said. "Now the question is how, exactly, a male bird determines the fertility status of potential partners."

David Williamson | EurekAlert!
Further information:
http://www.unc.edu

More articles from Life Sciences:

nachricht Stiffness matters
22.02.2018 | Albert-Ludwigs-Universität Freiburg im Breisgau

nachricht Separate brain systems cooperate during learning, study finds
22.02.2018 | Brown University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Developing reliable quantum computers

International research team makes important step on the path to solving certification problems

Quantum computers may one day solve algorithmic problems which even the biggest supercomputers today can’t manage. But how do you test a quantum computer to...

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Stiffness matters

22.02.2018 | Life Sciences

Magnetic field traces gas and dust swirling around supermassive black hole

22.02.2018 | Physics and Astronomy

First evidence of surprising ocean warming around Galápagos corals

22.02.2018 | Earth Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>