Mother birds 'engineer' their offspring

May 23, 2007

Bird species that have relatively long incubation periods and short nestling periods for their body size have higher concentration of androstenedione than those species whose developmental time is shifted towards relatively longer stays in the nest than in the egg. This is an advantage depending on the predators. There is a relationship between egg levels of androstenedione and colony size, suggesting that mothers prepare their offspring for the social conditions.

Current research emphasizes the role of maternal effects in fostering the adaptation of organisms to a changing environment. In birds, mothers pass androgens to their eggs, and these hormones have been shown to influence the development and behavior of nestlings. Since these effects may persist in adulthood, it has been suggested that avian mothers may engineer, so to speak, the adult phenotype of their offspring.

Although abundant research in a variety of species has examined these questions, little is known on whether differences between species in levels of egg androgens are related to differences in the ecology of species.

Diego Gil, from the Spanish Museum of Natural History, and coauthors (Clotilde Biard, André Lacroix, Claire Spottiswoode, Nicola Saino, Marisa Puerta, and Anders P. Møller) from several universities in Europe, show in a paper in the June issue of The American Naturalist that several differences in avian life history have coevolved with differences in yolk androgens. Thus, the relative amount of time that a developing bird spends in the egg and in the nest is positively related to androstenedione, one of the main egg androgens. That is to say, bird species that have relatively long incubation periods and short nestling periods for their body size have higher concentration of androstenedione than those species whose developmental time is shifted towards relatively longer stays in the nest than in the egg.

Another pattern that emerges is a positive relationship between egg levels of androstenedione and colony size, suggesting that mothers prepare their offspring for the social conditions that they will experience as adults. These data provide evidence that facultative maternal effects at the individual level are linked to evolutionary transitions between species, suggesting a role of phenotypic plasticity in supporting adaptative patterns.

Source: University of Chicago

Explore further: Dairy farms asked to consider breeding no-horn cows

add to favorites email to friend print save as pdf

Related Stories

DARPA seeks new positioning, navigation, timing solutions

2 hours ago

The Defense Advanced Research Projects Agency (DARPA), writing about GPS, said: "The military relies heavily on the Global Positioning System (GPS) for positioning, navigation, and timing (PNT), but GPS access is easily blocked by methods such as jamming. In addition, many environments in which our mil ...

Lights out in Australia as Earth Hour kicks off

2 hours ago

The Sydney Harbour Bridge and the sails on the nearby Opera House went dark Saturday, as lights on landmarks around Australia were switched off for the global climate change awareness campaign Earth Hour.

Future US Navy: Robotic sub-hunters, deepsea pods

6 hours ago

The robotic revolution that transformed warfare in the skies will soon extend to the deep sea, with underwater spy "satellites," drone-launching pods on the ocean floor and unmanned ships hunting submarines.

Recommended for you

Dairy farms asked to consider breeding no-horn cows

20 hours ago

Food manufacturers and restaurants are taking the dairy industry by the horns on an animal welfare issue that's long bothered activists but is little known to consumers: the painful removal of budding horn ...

Italian olive tree disease stumps EU

Mar 27, 2015

EU member states are divided on how to stop the spread of a disease affecting olive trees in Italy that could result in around a million being cut down, officials said Friday.

China starts relocating endangered porpoises: Xinhua

Mar 27, 2015

Chinese authorities on Friday began relocating the country's rare finless porpoise population in a bid to revive a species threatened by pollution, overfishing and heavy traffic in their Yangtze River habitat, ...

A long-standing mystery in membrane traffic solved

Mar 27, 2015

In 2013, James E. Rothman, Randy W. Schekman, and Thomas C. Südhof won the Nobel Prize in Physiology or Medicine for their discoveries of molecular machineries for vesicle trafficking, a major transport ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.