Featured Research

from universities, journals, and other organizations

Testosterone Boosts Birds' Attractiveness, But Leads To Shorter Lifespan

Date:
May 28, 2006
Source:
North Dakota State University
Summary:
Dating and mating are unique for many species, but for dark-eyed junco songbirds, researchers led by North Dakota State University assistant biology professor Wendy Reed, Ph.D., found something new.

A study of dark-eyed junco songbirds, led by North Dakota State University biology professor Wendy Reed, Ph.D., found that testosterone had both beneficial and adverse effects on the bird population in the study.
Credit: Photo Will Clark

Dating and mating are unique for many species, but for dark-eyed junco songbirds, researchers led by North Dakota State University assistant biology professor Wendy Reed, Ph.D., found something new.

Related Articles


Published in the May issue of The American Naturalist, the team’s study found that male birds with extra testosterone were more attractive to females and produced more—but smaller—offspring. Smaller offspring had lower survival rates than larger offspring. The extra testosterone also made the male birds sing more sweetly and fly farther. The testosterone-laden birds proved irresistible to older, more experienced female juncos, but that attractiveness carried some risks. Elevated testosterone levels increased activity—possibly attracting more predators—made the male, dark-eyed juncos more susceptible to disease and shortened their lifespan. “They had lower immune function and paid a cost with lower survival rates,” said Reed.

The increased testosterone also made the dark-eyed male juncos less attentive parents to their offspring as they made fewer nest visits, resulting in less food delivered and less time spent at the nest. The research team monitored more than 400 junco nests in the Appalachian Mountains of Virginia for nine breeding seasons. One group of dark-eyed juncos in the study received tubes implanted under the skin which contained testosterone and the control group of birds received implants that were left empty. Implants were removed from birds recaptured at the end of each breeding season.

Study results are featured by the American Association for the Advancement of Science, in a podcast called Testosterone Tradeoff at http://www.scienceupdate.com/index.cfm. The podcast notes that such feathered Casanovas have a better sex life, but a shorter one than birds not receiving the extra testosterone in the study. Reed led the research as part of her postdoctoral work.

The study is titled “Physiological Effects on Demography: A Long-Term Experimental Study of Testosterone’s Effect on Fitness.” Investigators in addition to Reed include: M.E. Clark, NDSU; P.G. Parker, University of Missouri; S.A. Raouf, University of Washington; M. Arguedas, Ohio State University; D.S. Monk, Washington State University; E. Snajdr, V. Nolan Jr., and E.D. Ketterson, Indiana University.

For more information, see:
“Physiological Effects on Demography: A Long-Term Experimental Study of Testosterone's Effects on Fitness.” The American Naturalist. May 2006, Vol. 167, No. 5, pgs 667-683. http://www.journals.uchicago.edu/AN/journal/issues/v167n5/41049/41049.html


Story Source:

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


Cite This Page:

North Dakota State University. "Testosterone Boosts Birds' Attractiveness, But Leads To Shorter Lifespan." ScienceDaily. ScienceDaily, 28 May 2006. <www.sciencedaily.com/releases/2006/05/060526083618.htm>.
North Dakota State University. (2006, May 28). Testosterone Boosts Birds' Attractiveness, But Leads To Shorter Lifespan. ScienceDaily. Retrieved December 20, 2014 from www.sciencedaily.com/releases/2006/05/060526083618.htm
North Dakota State University. "Testosterone Boosts Birds' Attractiveness, But Leads To Shorter Lifespan." ScienceDaily. www.sciencedaily.com/releases/2006/05/060526083618.htm (accessed December 20, 2014).

Share This


More From ScienceDaily



More Plants & Animals News

Saturday, December 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Researchers Test Colombian Village With High Alzheimer's Rates

Researchers Test Colombian Village With High Alzheimer's Rates

AFP (Dec. 19, 2014) In Yarumal, a village in N. Colombia, Alzheimer's has ravaged a disproportionately large number of families. A genetic "curse" that may pave the way for research on how to treat the disease that claims a new victim every four seconds. Duration: 02:42 Video provided by AFP
Powered by NewsLook.com
Monarch Butterflies Descend Upon Mexican Forest During Annual Migration

Monarch Butterflies Descend Upon Mexican Forest During Annual Migration

Reuters - Light News Video Online (Dec. 19, 2014) Millions of monarch butterflies begin to descend onto Mexico as part of their annual migration south. Rough Cut (no reporter narration) Video provided by Reuters
Powered by NewsLook.com
The Best Protein-Filled Foods to Energize You for the New Year

The Best Protein-Filled Foods to Energize You for the New Year

Buzz60 (Dec. 19, 2014) The new year is coming and nothing will energize you more for 2015 than protein-filled foods. Fitness and nutrition expert John Basedow (@JohnBasedow) gives his favorite high protein foods that will help you build muscle, lose fat and have endless energy. Video provided by Buzz60
Powered by NewsLook.com
Birds Might Be Better Meteorologists Than Us

Birds Might Be Better Meteorologists Than Us

Newsy (Dec. 19, 2014) A new study suggests a certain type of bird was able to sense a tornado outbreak that moved through the U.S. a day before it hit. Video provided by Newsy
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