Navigation Links
Uncertainty drives the evolution of 'cooperative breeding' in birds
Date:8/16/2007

Rather than striking out to start a family of their own, members of some bird species will stick around longer to help a relative raise their young. Now, researchers report evidence that in African starlings such altruistic tendencies are most common among species that live in savannas, where the rainfall in any given year is virtually impossible to predict. The findings appear online August 16 in the journal Current Biology, a publication of Cell Press.

When the unpredictability of your environment is high, you dont know in advance what conditions you will be facing when the next breeding season rolls around, said Dustin Rubenstein of the University of California, Berkeley and the Cornell Laboratory of Ornithology. Faced with this uncertainty, it pays, evolutionarily speaking, to live and breed in social groups that will help you weather the bad times and make the most of the good times. Living in cooperative family groups may be like a form of insurance against the unpredictable nature of the environment that allows individuals to maximize their reproductive success over the course of their lifetimes.

Over the past few decades, mounting evidence has shown that many species of cooperatively breeding birds live in semi-arid tropical and sub-tropical environments, particularly in sub-Saharan Africa and Australia. Although that pattern suggested that the environment might explain the behavior, few studies showed a strong relationship between the incidence of cooperative breeding among species and any particular environmental feature, the researchers noted.

In the new study, the researchers examined the pattern of breeding behavior exhibited by 45 species of African starlings in relation to the environments in which they liveincluding savannas, deserts and tropical forestswhile controlling for the evolutionary relationships among them. They also examined the rainfall patterns typical of each of those environments in 47 African countries as far back as 147 years ago.

They found evidence that different starling species have independently evolved the cooperative breeding system upon moving to savannas, where they showed that the amount of year-to-year variation in rainfall is greatest. Rubensteins group suggested that cooperative breeding is probably advantageous in environments that vary over time because it allows for reproduction in harsh years, as well as sustained breeding during benign years.

Such a strategy might become more widespread in an increasingly uncertain future, the researchers suggested.

Some researchers have argued that climate change will lead to greater temporal environmental variability, Rubenstein said. That is, we might expect more extreme weather like severe droughts and devastating floods, and ultimately more variable environments than we see now. If this increase in variability occurs, many species of animalsincluding humanswill have to adapt to the increasing unpredictability of their environments. By studying how animals have already adapted to temporally variable and unpredictable environments, we can gain insights into how social behavior may change in the wake of climate change.


'/>"/>
Contact: Nancy Wampler
nwampler@cell.com
617-386-2121
Cell Press
Source:Eurekalert

Related biology news :

1. Unchecked DNA replication drives earliest steps toward cancer
2. Climate change drives widespread amphibian extinctions
3. Habitat microstructure drives salamander metamorphosis
4. Mindless autopilot drives people to underestimate food decisions
5. Buildup of damaged DNA in cells drives aging
6. A genetic gang of 4 drives spread of breast cancer
7. Molecular biology fills gaps in knowledge of bat evolution
8. Same mutation aided evolution in many fish species, Stanford study finds
9. Researchers trace evolution to relatively simple genetic changes
10. Family trees of ancient bacteria reveal evolutionary moves
11. Great White shark evolution debate involves WSU Lake Campus geology professor
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:4/6/2017)... , April 6, 2017 Forecasts ... ANPR, Document Readers, by End-Use (Transportation & Logistics, Government ... Oil, Gas & Fossil Generation Facility, Nuclear Power), Industrial, ... Other) Are you looking for a definitive ... ...
(Date:4/3/2017)...  Data captured by IsoCode, IsoPlexis Corporation,s ... statistically significant association between the potency of ... objective response of cancer patients post-treatment. The ... cancer patients will respond to CAR-T cell ... to improve both pre-infusion potency testing and cell ...
(Date:3/28/2017)... , March 28, 2017 ... Biometrics), Hardware (Camera, Monitors, Servers, Storage Devices), Software (Video ... and Region - Global Forecast to 2022", published by ... in 2016 and is projected to reach USD 75.64 ... 2017 and 2022. The base year considered for the ...
Breaking Biology News(10 mins):
(Date:7/20/2017)... ... July 20, 2017 , ... ... clinical trial sites and study participants truly unified. TrialKit, a native mobile app, ... CFR Part 11) research studies entirely on mobile devices. With TrialKit, clinical researchers ...
(Date:7/18/2017)... ... ... Blood centers traditionally see a dangerous drop of blood donations during the ... community blood centers as high schools are out and many frequent donors are on ... up with the South Texas Blood & Tissue Center (STBTC), a subsidiary ...
(Date:7/17/2017)... ... July 17, 2017 , ... ... solutions, today announced safety software company AB Cube has joined its ... segment to advance technology innovation across life sciences and healthcare. Under the ...
(Date:7/17/2017)... ... July 17, 2017 , ... DuPont Pioneer today announced ... website (openinnovation.pioneer.com) dedicated to connecting third-party innovators with DuPont Pioneer scientists is ... enabling technologies, biologicals and digital solutions. , “DuPont Pioneer is building on its ...
Breaking Biology Technology: