Featured Research

from universities, journals, and other organizations

One smart egg: Birds sense day length and change development

Date:
July 10, 2012
Source:
North Dakota State University
Summary:
This is one smart egg. Talk about adjusting your internal clock. New research shows that some chicks can sense day length, even while they are still in the egg, which in turn, affects how they develop.

North Dakota State University biological science researchers Dr. Mark Clark and Dr. Wendy Reed, along with NDSU students, conducted field research on Franklin's gulls at J. Clark Salyer National Wildlife Refuge and Lake Alice National Wildlife Refuge in north-central North Dakota along the Souris River. Their research, published in Functional Ecology, shows that the birds sense day length before hatching and change how they develop.
Credit: M.E. Clark, NDSU

This is one smart egg. Talk about adjusting your internal clock. New research at North Dakota State University, Fargo, shows that some chicks can sense day length, even while they are still in the egg, which in turn, affects how they develop.

Dr. Mark E. Clark, associate professor, and Dr. Wendy Reed, head of biological sciences at NDSU, found in their study that embryos in eggs appear to sense external environments and adjust how they develop. The research is being published in Functional Ecology, a British Ecological journal.

Franklin's gull is a bird that migrates long distances and requires precise timing. It winters along the west coast of South America until returning to the prairie wetlands of North America, where it nests in large colonies come springtime. The dark hood, gray wings and pink-tinted breast are a harbinger of spring to the people of the Northern Great Plains, who affectionately call it the prairie rose gull. Soon after large wetlands thaw, Franklin's gulls arrive to build floating nests from wetland vegetation to hold three green-and-black speckled eggs.

Inside these dark eggs, the developing chicks also sense spring days. "The growing embryos integrate signals from the nutrients provided to eggs by mothers with the amount of daylight," said Dr. Clark. "The signals let the chick know whether the egg was laid at the beginning, or at the end of the nesting period."

Clark and Reed note that chicks from eggs produced at the beginning of nesting take longer to hatch, but are larger than chicks from eggs laid at the end of nesting. Contrast that with eggs laid at the end of the nesting period, which hatch in less time, but at a smaller size.

"Chicks hatching later in the season have less time to grow, less time to become independent, and less time for flying lessons before they must migrate to South America in the fall," said Dr. Reed.

According to Dr. Clark, data indicate embryos in late season eggs appear to be sensing external environments and adjusting their development. These changes in development time and size may be important for chicks to successfully migrate.

Many birds, including Franklin's gulls, are arriving earlier on their breeding grounds. "This research suggests that the impacts of changing seasonal signals have far reaching effects on bird biology, including chick development," said Dr. Clark.

Researchers evaluated the ability of avian embryos to integrate cues of season from photoperiod and maternal environments present in eggs to produce season variation among phenotypes among Franklin's gull (Leucophaeus pipixcan) hatchlings.

Field research was conducted at the J. Clark Salyer National Wildlife Refuge and Lake Alice National Wildlife Refuge in north-central North Dakota along the Souris River. Researchers collected early and late season eggs, separating some into component parts and incubating others for short or long photoperiods. Upon hatching, chicks were evaluated for size and yolk sac reserves.

Results of the study show that hatchling size is sensitive both to egg contents provided by mothers and to photoperiod, and development time increases across the season. When cues of season from eggs are mismatched with cues from photoperiod, alternate phenotypes are created.

Clark and Reed also found that seasonal variation in egg size, yolk, albumen or shell content of the eggs does not account for the seasonal maternal egg effect on hatchling size. "We expect our results to initiate new studies on how vertebrate embryos integrate environmental cues with maternal effects and offspring responses to optimize the expression of offspring phenotype," said Clark.

Previous NDSU graduate students who participated in the research include Shawn Weissenfluh and Emily Davenport-Berg. Other NDSU students who assisted in the research include Nathaniel Cross, Peter Martin, Dan Larsen, Michelle Harviell and Andrew Nygaard, along with Petar Miljkovic from Grinnell College.

Research funding was provided by the National Science Foundation (IOS-0445848), the North Dakota Game and Fish Department and the U.S. Fish and Wildlife Service.


Story Source:

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


Journal Reference:

  1. Mark E. Clark, Wendy L. Reed. Seasonal interactions between photoperiod and maternal effects determine offspring phenotype in Franklin's gull. Functional Ecology, 2012; DOI: 10.1111/j.1365-2435.2012.02010.x

Cite This Page:

North Dakota State University. "One smart egg: Birds sense day length and change development." ScienceDaily. ScienceDaily, 10 July 2012. <www.sciencedaily.com/releases/2012/07/120710185416.htm>.
North Dakota State University. (2012, July 10). One smart egg: Birds sense day length and change development. ScienceDaily. Retrieved July 22, 2014 from www.sciencedaily.com/releases/2012/07/120710185416.htm
North Dakota State University. "One smart egg: Birds sense day length and change development." ScienceDaily. www.sciencedaily.com/releases/2012/07/120710185416.htm (accessed July 22, 2014).

Share This




More Plants & Animals News

Tuesday, July 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

San Diego Zoo Welcomes New, Rare Rhino Calf

San Diego Zoo Welcomes New, Rare Rhino Calf

Reuters - US Online Video (July 21, 2014) An endangered black rhino baby is the newest resident at the San Diego Zoo. Sasha Salama reports. Video provided by Reuters
Powered by NewsLook.com
Shark Sightings a Big Catch for Cape Tourism

Shark Sightings a Big Catch for Cape Tourism

AP (July 21, 2014) A rise in shark sightings along the shores of Chatham, Massachusetts is driving a surge of eager vacationers to the beach town looking to catch a glimpse of a great white. (July 21) Video provided by AP
Powered by NewsLook.com
$23.6 Billion Awarded To Widow In Smoking Lawsuit

$23.6 Billion Awarded To Widow In Smoking Lawsuit

Newsy (July 20, 2014) Cynthia Robinson claims R.J. Reynolds Tobacco Company hid the health and addiction risks of its products, leading to the death of her husband in 1996. Video provided by Newsy
Powered by NewsLook.com
A Centuries' Old British Tradition Is Far from a Swan Song

A Centuries' Old British Tradition Is Far from a Swan Song

AFP (July 19, 2014) As if it weren't enough that the Queen is the Sovereign of the UK and 15 other Commonwealth realms, she is also the owner of all Britain's unmarked swans. Duration: 02:18 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:
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