Female mammals follow their noses to the right matesMarch 18, 2009
Historically, most examples of female mate choice and its evolutionary consequences are found in birds. The classic case is the peacock's tail. The ornate tails do nothing to help peacocks survive. Rather, they emerged because peahens prefer to mate with males that have showy plumage.
Such vivid examples of female preferences in mammals are harder to find, leading to an assumption that mate choice plays a smaller role in mammals than in birds. But that's not necessarily the case, Clutton-Brock and McAuliffe conclude. Female mating preferences are likely to be just as important in mammals, though they may not be as obvious to human observers.
The researchers point out several factors that complicate the study of mammalian mate choice. One factor is the very nature of mammalian mating systems. Males compete fiercely with each other for access to female partners. Since the dominant males often chase away other males, it's hard to tell if females are choosing to mate with certain males, or are merely mating with them by default.
"The most convincing evidence for female mate choice in mammals comes from studies of captive mammals -carried out under controlled conditions where the effects of male competition can be excluded -," Clutton-Brock and McAuliffe write.
Lab studies of olfactory signaling, they say, may provide the best evidence for female mate choice in mammals. Unlike birds, many mammal species are sexually active at night. So mammals may be less inclined than birds to base preferences on visual cues. Instead, females of many mammalian species may be more likely to choose males using olfactory cues.
Research has shown that female mammals commonly investigate scent marks left by males. Females also show a preference to mate with males who scent mark more frequently.
Just what can a female learn about a male through his scent? Plenty, say Clutton-Brock and McAuliffe.
Recent studies have shown that mammalian females use scent to pick out genetically dissimilar males. Parents with dissimilar genes in a certain part of the genome tend to produce healthier offspring. So male mammals advertise their genotype via scent, and females pick up the signal and preferentially mate with dissimilar males. This ability to sniff out a good genetic match has been found in mice and humans.
Other studies of several rodent species have found that females dislike odors of males who are infected with parasites, and may avoid mating with them. Since resistance to parasites is often a genetic trait, choosing a parasite-free mate may be beneficial to offspring.
Study of olfactory mating cues is still in its infancy, Clutton-Brock and McAuliffe say. But they believe that this line of research will continue to reveal much about mammalian mate choice.
"[I]t is possible that in some mammals, males produce olfactory signals that match the elaboration and complexity of the peacock's tail - or the sedge warbler's song -," Clutton-Brock and McAuliffe write.
University of Chicago Press Journals
Related Mate Choice Current Events and Mate Choice News Articles
Female mice do not avoid mating with unhealthy males
Female mice are attracted more strongly to the odour of healthy males than unhealthy males.
Secret wing colors attract female fruit flies
Bright colours appear on a fruit fly's transparent wings against a dark background as a result of light refraction. Researchers from Lund University in Sweden have now demonstrated that females choose a mate based on the males' hidden wing colours.
How female flies know when to say 'yes'
A fundamental question in neurobiology is how animals, including humans, make decisions. A new study publishing in the open access journal PLOS Biology on October 7 reveals how fruit fly females make a very important decision: to either accept or reject male courtship.
Skin coloring of rhesus macaque monkeys linked to breeding success, new study shows
Skin colour displayed amongst one species of monkey provides a key indicator of how successfully they will breed, a new study has shown.
The genes tell crows to choose partners that look alike
Crows like to select mates that look alike. In a large-scale genomic study, published in Science today, a team of researchers led by Uppsala University found that this behaviour might be rooted in their genetic make-up, revealing a likely common evolutionary path that allows for separating populations into novel species.
Study finds wild coho may seek genetic diversity in mate choice
A new study by researchers at Oregon State University suggests that wild coho salmon that choose mates with disease-resistant genes different from their own are more likely to produce greater numbers of adult offspring returning to the river some three years later.
White silk wrappings key to female spider's heart
It's not only what's inside the nuptial gift that a potential suitor brings to a female Paratrechalea ornata spider that counts. It's the whole package, white silk wrappings and all, that can give one male spider the edge over another.
Biological Fitness Trumps Other Traits in Mating Game
When a new species emerges following adaptive changes to its local environment, the process of choosing a mate can help protect the new species' genetic identity and increase the likelihood of its survival.
Big feet preference in rural Indonesia defies one-size-fits-all theory of attractiveness
People in most cultures view women with small feet as attractive. Like smooth skin or an hourglass figure, petite feet signal a potential mate's youth and fertility.
Mate choice in mice is heavily influenced by paternal cues
Mate choice is a key factor in the evolution of new animal species. The choice of a specific mate can decisively influence the evolutionary development of a species.
More Mate Choice Current Events and Mate Choice News Articles