Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

One Smart Egg: Birds Sense Day Length and Change Development

12.07.2012
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, available in early view online.

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.

North Dakota State University, Fargo, is a student focused, land-grant, research university – an economic engine that educates students, conducts primary research, creates new knowledge and advances technology. NDSU is among the top 108 universities in the country with very high research activity, as determined by the Carnegie Commission on Higher Education.

A British Ecological Society journal, Functional Ecology publishes high impact papers on organismal ecology, including physiological, behavioural and evolutionary ecology.

Carol Renner | Newswise Science News
Further information:
http://www.ndsu.edu

More articles from Life Sciences:

nachricht Fine organic particles in the atmosphere are more often solid glass beads than liquid oil droplets
21.04.2017 | Max-Planck-Institut für Chemie

nachricht Study overturns seminal research about the developing nervous system
21.04.2017 | University of California - Los Angeles Health Sciences

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

Im Focus: Quantum-physical Model System

Computer-assisted methods aid Heidelberg physicists in reproducing experiment with ultracold atoms

Two researchers at Heidelberg University have developed a model system that enables a better understanding of the processes in a quantum-physical experiment...

Im Focus: Glacier bacteria’s contribution to carbon cycling

Glaciers might seem rather inhospitable environments. However, they are home to a diverse and vibrant microbial community. It’s becoming increasingly clear that they play a bigger role in the carbon cycle than previously thought.

A new study, now published in the journal Nature Geoscience, shows how microbial communities in melting glaciers contribute to the Earth’s carbon cycle, a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

7th International Conference on Crystalline Silicon Photovoltaics in Freiburg on April 3-5, 2017

03.04.2017 | Event News

 
Latest News

New quantum liquid crystals may play role in future of computers

21.04.2017 | Physics and Astronomy

A promising target for kidney fibrosis

21.04.2017 | Health and Medicine

Light rays from a supernova bent by the curvature of space-time around a galaxy

21.04.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>