Featured Research

from universities, journals, and other organizations

Scientists identify why some fathers are left holding the baby

Date:
March 12, 2013
Source:
University of Sheffield
Summary:
A century old mystery as to why, for some animals, it's the father rather than the mother that takes care of their young has been cracked by scientists.

Sanderling - Calidris alba, Crete.
Credit: © tassos1966 / Fotolia

A century old mystery as to why, for some animals, it's the father rather than the mother that takes care of their young has been cracked by researchers at the University of Sheffield.

Experts from the University, in collaboration with the University of Bath and Veszprém (Hungary) found that role reversal was caused by an imbalance in the numbers of males relative to females.

The findings have been published in the journal Nature Communications.

Darwin noted in 1871 that in most animals, it is the females that spend most time looking after the young, whilst males focus on competing with each other for females.

Evolutionary biologists argued that this was due to the female investing significant amounts of energy in producing eggs, and in the case of mammals, giving birth, and so it is in their interests to ensure their offspring's survival by caring for them.

However, in some species, such as seahorses, the sex roles are reversed where the females produce the eggs but then leave it to their male mates to care for their offspring.

Dr András Liker, Marie Curie Research Fellow from the University of Sheffield's Department of Animal and Plant Sciences, said: "Sex-role reversal has been a formidable puzzle for evolutionary biologists ever since Darwin. Our study is the first supporting the idea that sex ratio plays an important part in the evolution of role reversal."

The researchers studied birds where the sex roles were reversed and found there was a higher ratio of males to females in the population, compared with the usual situation where females care for offspring.

Professor Tamás Székely, Professor of Biodiversity at the University of Bath, explained: "The research group has investigated sex role reversal for over 20 years, and was extremely pleasing to see such a clear cut result.

"Mathematical models suggest that these animals' behaviour is strongly influenced by their social environment, and our findings support these predictions.

"When there are lots of males in a population, it's harder to find females, so it benefits males to stay with their mate and look after the young.

"However, the females often take advantage of this and leave the male holding the baby, whilst they go and find another mate."

Females in the sex role reversed species also take on the traditional male role of being bigger and compete with each other for males.

The role reversal isn't usually seen in mammals: since males can't produce milk it's not as easy for them to take over the parenting completely. However changes in sex role behaviour have been observed in humans when the sex ratio is imbalanced.


Story Source:

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


Journal Reference:

  1. András Liker, Robert P. Freckleton, Tamás Székely. The evolution of sex roles in birds is related to adult sex ratio. Nature Communications, 2013; 4: 1587 DOI: 10.1038/ncomms2600

Cite This Page:

University of Sheffield. "Scientists identify why some fathers are left holding the baby." ScienceDaily. ScienceDaily, 12 March 2013. <www.sciencedaily.com/releases/2013/03/130312121842.htm>.
University of Sheffield. (2013, March 12). Scientists identify why some fathers are left holding the baby. ScienceDaily. Retrieved July 28, 2014 from www.sciencedaily.com/releases/2013/03/130312121842.htm
University of Sheffield. "Scientists identify why some fathers are left holding the baby." ScienceDaily. www.sciencedaily.com/releases/2013/03/130312121842.htm (accessed July 28, 2014).

Share This




More Plants & Animals News

Monday, July 28, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Sea Turtle Hatchlings Emerge from Nest

Raw: Sea Turtle Hatchlings Emerge from Nest

AP (July 27, 2014) — A live-streaming webcam catches loggerhead sea turtle hatchlings emerging from a nest in the Florida Keys. (July 27) Video provided by AP
Powered by NewsLook.com
Trees Could Save More Than 850 Lives Each Year

Trees Could Save More Than 850 Lives Each Year

Newsy (July 27, 2014) — A national study conducted by the USDA Forest Service found that trees collectively save more than 850 lives on an annual basis. Video provided by Newsy
Powered by NewsLook.com
What's To Blame For Worst Ebola Outbreak In History?

What's To Blame For Worst Ebola Outbreak In History?

Newsy (July 27, 2014) — A U.S. doctor has tested positive for the deadly Ebola virus, as the worst-ever outbreak continues to grow. Video provided by Newsy
Powered by NewsLook.com
The New York Times Backs Pot Legalization

The New York Times Backs Pot Legalization

Newsy (July 27, 2014) — The New York Times has officially endorsed the legalization of marijuana, but why now, and to what end? 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:
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