Featured Research

from universities, journals, and other organizations

In Nature Vs. Nurture Debate, Biologists Find That Genes Drive Cliff Swallows In Group Choice

Date:
December 27, 2000
Source:
University Of Tulsa
Summary:
In the classic debate of nature versus nurture, University of Tulsa researchers Charles and Mary Brown have scored one for heredity -- at least when it comes to cliff swallows. The Browns say their study shows that genes guide cliff swallows when they select the size of colony in which to live. They say this the first report of heredity influencing an animal's choice of a social system.

In the classic debate of nature versus nurture, University of Tulsa researchers Charles and Mary Brown have scored one for heredity -- at least when it comes to cliff swallows.

The Browns say their study shows that genes guide cliff swallows when they select the size of colony in which to live. They say this the first report of heredity influencing an animal's choice of a social system.

The study, "Heritable Basis for Choice of Group Size in a Colonial Bird," appears in the Dec. 19 issue of Proceedings of the National Academy of Sciences.

"We clearly found that individuals have a genetic basis as to where they choose to live," says Charles Brown, a biology professor who has studied cliff swallows along the Platte River in Nebraska for 19 years.

In 1997 and 1998 the Browns switched nearly 2,000 very young birds from nests in big colonies to nests in small colonies, and vice versa. The two biologists discovered that when these birds returned about nine months later to settle into their own nests and start their own families, they chose the same colony size as that in which they were born.

"Our study suggests that there is a genetic difference between birds that choose to live in large groups versus birds that choose to live in small colonies," he says.

The cliff swallows in their study area nest in colonies that range in size from two nests to more than 3,000 nests. Mud nests are usually found on bridges and cliffs.

Each summer Charles Brown and his wife, Mary, a research associate in TU's biological sciences department, band birds and recapture previously banded swallows for many reasons: to determine life span, migration patterns, sex and health. Since 1982 they have banded about 120,000 birds.

For this study, they moved birds that were five days old, placing identification bands on their legs and exchanging half the brood in a nest in a big colony with half the brood in a nest in a small colony. A cliff swallow nest usually has from two to five hatchlings. The parents raised the foster hatchlings along with the other chicks.

Baby cliff swallows hatch in June. Later in the fall they migrate to South America and return north in May. Brown says 36 percent of the 1,968 birds that were banded were caught in the study area where they were born. The Browns had already observed that among the birds that were part of their routine yearly study, offspring tended to select colony sizes similar to those of their parents.

Birds were caught using mist nets, and the Browns recorded the nest preference of the cliff swallows which they had switched between colonies as babies in 1997-98. "Then we were able to see which size colony they settled in and compare their choice to the colony in which they were raised and to the colony in which they were born," says Brown.

They found that birds born and raised in a large colony return to a large colony, and birds born in a large colony -- but raised in a small colony -- also return to a large colony.

Similarly, birds born and raised in a small colony return to a small colony, and birds born in a small colony -- but raised in a large colony -- also return to a small colony.

"They return to where they were born irrespective of when they were raised," says Brown. "They are picking the colonies that their parents picked; so it is not environment, it is genes that appear to be dictating their choice."

He says the hatchling exchange approach rules out environmental effects, such as sites with better food sources or nesting materials, that one might assume bear on a bird's decision.

The Browns, authors of the book "Coloniality in the Cliff Swallow: The Effect of Group Size on Social Behavior," say the benefits and drawbacks of living in groups are well understood, but they wanted to begin to find the underlying basis for the birds' selection of a large or a small aggregation.


Story Source:

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


Cite This Page:

University Of Tulsa. "In Nature Vs. Nurture Debate, Biologists Find That Genes Drive Cliff Swallows In Group Choice." ScienceDaily. ScienceDaily, 27 December 2000. <www.sciencedaily.com/releases/2000/12/001226081956.htm>.
University Of Tulsa. (2000, December 27). In Nature Vs. Nurture Debate, Biologists Find That Genes Drive Cliff Swallows In Group Choice. ScienceDaily. Retrieved October 1, 2014 from www.sciencedaily.com/releases/2000/12/001226081956.htm
University Of Tulsa. "In Nature Vs. Nurture Debate, Biologists Find That Genes Drive Cliff Swallows In Group Choice." ScienceDaily. www.sciencedaily.com/releases/2000/12/001226081956.htm (accessed October 1, 2014).

Share This



More Plants & Animals News

Wednesday, October 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Cultural Learning In Wild Chimps Observed For The First Time

Cultural Learning In Wild Chimps Observed For The First Time

Newsy (Oct. 1, 2014) — Cultural transmission — the passing of knowledge from one animal to another — has been caught on camera with chimps teaching other chimps. Video provided by Newsy
Powered by NewsLook.com
Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Earth Has Lost Half Its Vertebrate Wildlife Since 1970: WWF

Newsy (Sep. 30, 2014) — A new study published by the World Wide Fund for Nature found that more than half of the world's wildlife population has declined since 1970. Video provided by Newsy
Powered by NewsLook.com
Dolphins Might Use Earth's Magnetic Field As A GPS

Dolphins Might Use Earth's Magnetic Field As A GPS

Newsy (Sep. 30, 2014) — A study released Monday suggests dolphins might be able to sense the Earth's magnetic field and possibly use it as a means of navigation. Video provided by Newsy
Powered by NewsLook.com
How To Battle Stink Bug Season

How To Battle Stink Bug Season

Newsy (Sep. 30, 2014) — Homeowners in 33 states grapple with stink bugs moving indoors at this time of year. Here are a few tips to avoid stink bug infestations. 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