Featured Research

from universities, journals, and other organizations

Birds in uncertain climates are more likely to stray from their mates

Date:
February 16, 2012
Source:
National Evolutionary Synthesis Center (NESCent)
Summary:
Married people may pledge to stay faithful through good times and bad, but birds sing a different tune -- when weather is severe or uncertain, birds are more likely to stray from their mates, says a new study.

Black-capped chickadee. Married people may pledge to stay faithful through good times and bad, but birds sing a different tune -- when weather is severe or uncertain, birds are more likely to stray from their mates.
Credit: Michael Mill / Fotolia

Married people may pledge to stay faithful through good times and bad, but birds sing a different tune -- when weather is severe or uncertain, birds are more likely to stray from their mates, says a new study by researchers working at the National Evolutionary Synthesis Center and Columbia University.

The results could mean more marital strife for birds coping with climate change, the researchers say.

Divorce and infidelity are a normal part of life for most birds, which typically nest with one partner for a few months or years, but may have chicks out of 'wedlock' or move on to new mates between breeding seasons.

"Most apparently monogamous birds end up having multiple partners," said lead author Carlos Botero, who conducted the study while at the National Evolutionary Synthesis Center, and is now a postdoctoral fellow at the Initiative in Biocomplexity at North Carolina State University.

Botero and his colleague Dustin Rubenstein of Columbia University wanted to find out if bird divorce and infidelity were more or less likely in dicey climates.

To find out, they studied records of the mating habits of hundreds of bird species, focusing on species where males and females work together to raise their chicks -- a large data set that included swallows, chickadees, blue birds, falcons, warblers, sparrows, ducks, geese and gulls.

For each species in their data set, they measured the rate of infidelity -- defined as the fraction of nests containing chicks resulting from an 'affair' -- as well as the rate of divorce, or the fraction of birds that changed partners between breeding seasons.

When they combined this data with temperature and precipitation records from weather stations near each species' nesting sites, they found something interesting -- birds that breed in changeable climates were more likely to cheat.

Infidelity was more common in species that breed in areas with more dramatic seasonal swings between warm and cold. When seasons are severe, promiscuity may pay off as a way of increasing the genetic diversity of the chicks, Botero said. "Mating with multiple partners improves the chances that at least one chick will have the genes to cope with the variable conditions to come," he explained.

The effect was greater for divorce. Birds in unpredictable climates were more likely to cast off their current mate and seek a new partner for the next breeding season, even at the expense of losing valuable breeding time before they paired up again.

"The quality of a potential mate depends on the context," Botero explained. In the Galapagos Islands, for example, finches with bigger beaks are better at finding food during dry periods, when larger, drier, harder-to-crush seeds are more important, whereas finches with smaller beaks do better during wet periods.

The perfect partner during one set of conditions may be a so-so mate at another. But when the length, timing or intensity of annual weather cycles is less certain, it may be harder for a bird to predict, based on conditions during the courting phase, what conditions are likely to be like during the chick-rearing phase. "The more unpredictable the environment is, the more likely birds are to make mistakes [in picking a mate], and the more likely they are to divorce," Botero said.

What does this mean for birds coping with climate change?

"As a result of climate change weather patterns have become more unpredictable, and the frequency of extreme weather events has increased," Botero said.

Whether the findings apply to humans is still unknown, but in birds "we would expect marital strife will become much more common," he added.

The results will appear in the February 16th issue of PLoS ONE.


Story Source:

The above story is based on materials provided by National Evolutionary Synthesis Center (NESCent). Note: Materials may be edited for content and length.


Journal Reference:

  1. Carlos A. Botero, Dustin R. Rubenstein. Fluctuating Environments, Sexual Selection and the Evolution of Flexible Mate Choice in Birds. PLoS ONE, 2012; 7 (2): e32311 DOI: 10.1371/journal.pone.0032311

Cite This Page:

National Evolutionary Synthesis Center (NESCent). "Birds in uncertain climates are more likely to stray from their mates." ScienceDaily. ScienceDaily, 16 February 2012. <www.sciencedaily.com/releases/2012/02/120216185406.htm>.
National Evolutionary Synthesis Center (NESCent). (2012, February 16). Birds in uncertain climates are more likely to stray from their mates. ScienceDaily. Retrieved July 29, 2014 from www.sciencedaily.com/releases/2012/02/120216185406.htm
National Evolutionary Synthesis Center (NESCent). "Birds in uncertain climates are more likely to stray from their mates." ScienceDaily. www.sciencedaily.com/releases/2012/02/120216185406.htm (accessed July 29, 2014).

Share This




More Plants & Animals News

Tuesday, July 29, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Deadly Ebola Virus Threatens West Africa

Deadly Ebola Virus Threatens West Africa

AP (July 28, 2014) West African nations and international health organizations are working to contain the largest Ebola outbreak in history. It's one of the deadliest diseases known to man, but the CDC says it's unlikely to spread in the U.S. (July 28) Video provided by AP
Powered by NewsLook.com
Traditional African Dishes Teach Healthy Eating

Traditional African Dishes Teach Healthy Eating

AP (July 28, 2014) Classes are being offered nationwide to encourage African Americans to learn about cooking fresh foods based on traditional African cuisine. The program is trying to combat obesity, heart disease and other ailments often linked to diet. (July 28) Video provided by AP
Powered by NewsLook.com
Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Asteroid's Timing Was 'Colossal Bad Luck' For The Dinosaurs

Newsy (July 28, 2014) The asteroid that killed the dinosaurs struck at the worst time for them. A new study says that if it hit earlier or later, they might've survived. Video provided by Newsy
Powered by NewsLook.com
Raw: Sea Turtle Hatchlings Emerge from Nest

Raw: Sea Turtle Hatchlings Emerge from Nest

AP (July 27, 2014) A live-streaming webcam catches loggerhead sea turtle hatchlings emerging from a nest in the Florida Keys. (July 27) Video provided by AP
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:
from the past week

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