Mating that causes injuries

Feb 20, 2009

Researchers at Uppsala University can now show that what is good for one sex is not always good for the other sex. In fact, evolutionary conflicts between the two sexes cause characteristics and behaviors that are downright injurious to the opposite sex. The findings are being published in the scientific journal Current Biology.

In both males and females in the animal world it is common - much more common that one might like to think - for one sex to evince characteristics and properties that are injurious to individuals of the other sex, according to Professor Göran Arnqvist at the Department of Ecology and Evolution, who adds:

"One especially tricky case involves species where the males have mating organs that are supplied with hooks, barbs, and flukes that cause internal injuries in females during mating. This is extremely common among insects, but it also occurs in many other animal groups."

The Uppsala scientists have studied seed beetles and their mating behavior. Göran relates that the males' mating organ is rather similar to a medieval spiked club and that it causes severe wounds in females during mating. But since it is never a good idea for a male merely to injure a female, the researchers have assumed that these structures serve another purpose and that the injury is an unfortunate side effect.

"Females' injuries as such do not benefit the male she mated with. It has been suggested rather that the injuries are a side effect of other benefits the males reap from the barbs. Now, for the first time, we are able to show that this is the case," says Göran Arnqvist.

Despite these costs, females mate with multiple males.

"We also show that males with long barbs cause more severe injuries to females, but also that these males have a greater rate of fertilization success," says Göran Arnqvist.

The barbs are thus extremely important to males in their competition to be able to fertilize an egg. When females mate with two males, it is more often the male with the longer barbs that fertilizes her eggs.

Source: Uppsala University

Explore further: Largest genetic survey to date shows major success of giant panda breeding programs

add to favorites email to friend print save as pdf

Related Stories

Using mosquitos to decrease the mosquito population

Jul 15, 2014

Who would have thought of mosquitoes being put to work to help decrease and control the mosquito population? University of Kentucky professor and researcher Stephen Dobson and his former graduate student, ...

Biologists link sexual selection and placenta formation

Jul 09, 2014

Sexual selection refers to species' selection for traits that are attractive to the opposite sex. This special type of natural selection enhances opportunities to mate, the tail of male peacocks being an ...

Transgender algae reveal evolutionary origin of sexes

Jul 08, 2014

Throughout evolution, living things have repeatedly developed physically distinct sexes, but how does this actually happen? A discovery in the multicellular green alga, Volvox carteri, has revealed the genetic ...

Recommended for you

User comments : 0