Study brings greater clarity to sex roles

Apr 15, 2014
Study brings greater clarity to sex roles
Sexual stereotypes revealed by the red junglefowl.

Glossy magazines and TV reality shows often portray males as the gender that strays and females as the gender that's picky.

They are sexual stereotypes rooted in the science of UK geneticist Angus Bateman who, in 1948, published a about among males and females.

Bateman's principles have often been challenged by researchers but a new University of Queensland study has shown the principles to be correct, if somewhat overestimated.

Dr Julie Collet, from UQ's School of Biological Sciences, said the research increased understanding of the evolution of and the differences between males and females.

"In most species, males have evolved to be more competitive to increase their number of sexual partners and ," she said.

"Females are usually limited by the time and energy invested in producing offspring rather than the availability of mates and can often select from a range of suitors.

"This leads to a perpetuation of the competitive traits in males and evolves into greater differences between males and females."

Bateman's principles suggest a direct relationship between mating success and reproductive success - the number of offspring produced - but this study shows a more complex relationship.

The researchers studied groups of red junglefowl (Gallus gallus), the wild ancestor of the domestic chicken, and recorded all mating events and offspring produced.

"Previous studies overlooked mating events that did not result in offspring," Dr Collet said.

"When we included unfruitful mating in the equation it resulted in a weaker relationship between mating success and reproductive success."

The results of this study were consistent with the theory of Bateman's principles, but showed a less dramatic difference between males and females than other estimates.

"In many species, including humans, there is potentially more variability in the number of offspring per male than per female," Dr Collet said.

"Our study supported this but showed that the level of sexual selection on males was not as high as previously estimated."

The study also showed that Bateman's principles could be flipped around and applied to females to show a strong relationship between and mating success.

"Females who are more reproductively successful are more attractive to males, leading to greater for these females," Dr Collet said.

"To gain a more complete understanding of the evolution of sex roles and the differences between and it is necessary to rethink the traditional approaches."

Explore further: Tiny male spiders can get a leg over—as long as they're picky

More information: Julie M. Collet, Rebecca F. Dean, Kirsty Worley, David S. Richardson, and Tommaso Pizzari. The measure and significance of Bateman's principles. Proc. R. Soc. B May 7, 2014 281 1782 20132973; DOI: 10.1098/rspb.2013.2973 1471-2954

add to favorites email to friend print save as pdf

Related Stories

Multiple mates worth the risk for female prairie dogs

Dec 04, 2013

Mating with more than one male increases reproductive success for female prairie dogs, despite an increase in risks. This is according to a new study published in The Journal of Mammalogy by behavioral ecolog ...

Recommended for you

Cats put sight over smell in finding food

15 hours ago

Cats may prefer to use their eyes rather than follow their nose when it comes to finding the location of food, according to new research by leading animal behaviourists.

Feds spot third baby orca born recently to imperiled pods

16 hours ago

(AP)—U.S. scientists following endangered killer whales from a research vessel have spotted a baby orca off the coast of Washington state, the third birth documented this winter but still leaving the population ...

Bumblebees make false memories too

18 hours ago

It's well known that our human memory can fail us. People can be forgetful, and they can sometimes also "remember" things incorrectly, with devastating consequences in the classroom, courtroom, and other ...

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.