In what may help understand why geeks get the girls, a study on the Satin Bowerbird’s mating rituals has for the first time directly linked a male's cognitive performance to his luck with the ladies.
"Males that are better problem-solvers are mating with more females," New Scientist magazine quoted says Jason Keagy, a behavioural ecologist at the University of Maryland in College Park, as saying.
The researcher points out that males construct elaborate shrines – bowers – to woo females, who judge them by the quality of their ornately decorated grass bowers, and elaborate mating dances.
Keagy says that both features let males to show off their smarts.
For their study, Keagy and colleagues developed a bowerbird IQ test to record which males attracted the most females over two breeding seasons.
The tests required males to remove red blocks, a colour they find odious, from their bowers in two different ways.
In one test, the researchers placed blocks under a clear plastic container, which birds had to knock off before removing the blocks. In the second test, they presented males with an unmoveable red block screwed into the ground.
The researchers observed that the smartest males determined that covering the block with leaves was the best way to obscure it.
According to Keagy, one possibility is that the tests reflect on duties connected to mating, and males that are better at problem-solving may construct more appealing bowers.
As to why do females favour more intelligent males, the researcher says that intelligence seems to act as an indicator of the genetic quality of a potential mate, and the genes he will pass onto his offspring.
"A male that has a well functioning brain is probably going to be good at surviving. It's almost like a way of interpreting all this information about the genetic quality of a male," Keagy says.
Two recent studies conducted by Geoffrey Miller, of the University of New Mexico in Albuquerque, and his wife Rosalind Arden, of King's College in London, have also shown that more intelligent men among Vietnam veterans experienced fewer health problems, such as hernias and cataracts, than less intelligent men.
They also found performance on intelligence to be associated with healthy sperm in a smaller subset of vets.
A research article describing Keagy’s study has been published in the journal Animal Behaviour.