Featured Research

from universities, journals, and other organizations

It's no sweat for salt marsh sparrows to beat the heat if they have a larger bill

Date:
August 8, 2011
Source:
Smithsonian
Summary:
Birds use their bills largely to forage and eat, and these behaviors strongly influence the bill's shape and size. But the bill can play an important role in regulating the bird's body temperature by acting as a radiator for excess heat. A team of scientists have found that because of this, high summer temperatures have been a strong influence in determining bill size in some birds, particularly species of sparrows that favor salt marshes.

Birds use their bills largely to forage and eat, and these behaviors strongly influence the shape and size of a bird's bill. But the bill can play an important role in regulating the bird's body temperature by acting as a radiator for excess heat. A team of scientists have found that because of this, high summer temperatures have been a strong influence in determining bill size in some birds, particularly species of sparrows that favor salt marshes.

Related Articles


The team's findings are published in the scientific journal Ecography, July 20.

Scientists at the Smithsonian Migratory Bird Center at the Smithsonian's Conservation Biology Institute and colleagues examined five species of sparrow that inhabit salt marshes on the East, West and Gulf coasts of North America. While these marshes are very similar in makeup and structure, the main difference among them is summer temperatures. Focusing on 10 species and subspecies of tidal salt marsh sparrow, the team measured 1,380 specimens and found that the variation in the sparrows' bill size was strongly related to the variation in the daily high summer temperatures of their salt marsh breeding habitats -- the higher the average summer temperature, the larger the bill. Birds pump blood into tissue inside the bill at high temperatures and the body's heat is released into the air. Because larger bills have a greater surface area than smaller bills, they serve as more effective thermoregulatory organs under hot conditions. On average, the study found the bills of sparrows in marshes with high summer temperatures to be up to 90 percent larger than those of the same species in cooler marshes.

"It is known that blood flow is increased in poorly insulated extremities in some animals, like a seal's flippers, a rabbit's ears and the wattles of a turkey helping hot animals to cool down. The bill of a bird can function in much the same way allowing birds to dump heat," said Russ Greenberg, director of the Smithsonian Migratory Bird Center and lead author of the research. "Being able to cool down and not loose excess body moisture is particularly important since these birds live in an environment with direct sun and limited access to fresh water."

The scientific theory known as Allen's Rule states that warm-blooded species from colder climates usually have shorter limbs or appendages than the equivalent animals from warmer climates. The team's new findings are a new example of Allen's Rule that confirms the importance of physiological constraints on the evolution of vertebrate morphologies, even in bird bills.

The research team is working with physiologists from Brock University in Canada, employing thermal imaging to develop a more detail picture of how song sparrows that live in dunes and marshes along the Atlantic coast use their bills to stay cool.


Story Source:

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


Journal Reference:

  1. Russell Greenberg, Raymond Danner, Brian Olsen, David Luther. High summer temperature explains bill size variation in salt marsh sparrows. Ecography, 2011; DOI: 10.1111/j.1600-0587.2011.07002.x

Cite This Page:

Smithsonian. "It's no sweat for salt marsh sparrows to beat the heat if they have a larger bill." ScienceDaily. ScienceDaily, 8 August 2011. <www.sciencedaily.com/releases/2011/07/110720163518.htm>.
Smithsonian. (2011, August 8). It's no sweat for salt marsh sparrows to beat the heat if they have a larger bill. ScienceDaily. Retrieved November 1, 2014 from www.sciencedaily.com/releases/2011/07/110720163518.htm
Smithsonian. "It's no sweat for salt marsh sparrows to beat the heat if they have a larger bill." ScienceDaily. www.sciencedaily.com/releases/2011/07/110720163518.htm (accessed November 1, 2014).

Share This



More Plants & Animals News

Saturday, November 1, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Watch Baby Goose Survive A 400-Foot Cliff Dive

Watch Baby Goose Survive A 400-Foot Cliff Dive

Buzz60 (Oct. 31, 2014) For its nature series Life Story, the BBC profiled the barnacle goose, whose chicks must make a daredevil 400-foot cliff dive from their nests to find food. Jen Markham has the astonishing video. Video provided by Buzz60
Powered by NewsLook.com
World's Salamanders At Risk From Flesh-Eating Fungus

World's Salamanders At Risk From Flesh-Eating Fungus

Newsy (Oct. 31, 2014) The import of salamanders around the globe is thought to be contributing to the spread of a deadly fungus. Video provided by Newsy
Powered by NewsLook.com
Alcoholic Drinks In The E.U. Could Get Calorie Labels

Alcoholic Drinks In The E.U. Could Get Calorie Labels

Newsy (Oct. 31, 2014) A health group in the United Kingdom has called for mandatory calorie labels on alcoholic beverages in the European Union. Video provided by Newsy
Powered by NewsLook.com
Malaria Threat in Liberia as Fight Against Ebola Rages

Malaria Threat in Liberia as Fight Against Ebola Rages

AFP (Oct. 31, 2014) Focus on treating the Ebola epidemic in Liberia means that treatment for malaria, itself a killer, is hard to come by. MSF are now undertaking the mass distribution of antimalarials in Monrovia. Duration: 00:38 Video provided by AFP
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