New Scientist Breaking News – Sexual ornaments grow out of all proportion:
Sexual ornaments grow out of all proportion
22:00 22 May 2006
NewScientist.com news service
Patrick Barry

James Brown, University of New Mexico
Proceedings of the National Academy of Sciences

The male obsession with size appears to be universal, according to a new survey of animal species where males use ornamental body parts to attract females. The study showed that sexual ornaments – such as antlers or a peacock’s feathery display – become disproportionately large as body size increases.

Most body parts grow proportionally with the rest of the body as individuals of a species become larger, although scientists have long known that visual cues of reproductive prowess are a special case.

Now, in the largest survey to date, James Brown at the University of New Mexico, Albuquerque, US, and his colleagues have examined the proportions of 284 ornament-bearing species to see whether the tendency was truly universal. They found that in virtually every case, ornament size grew by roughly the square of the overall growth rate.

Surprisingly, whether the ornament also functioned as a weapon made little difference to its size. But even for purely decorative ornaments, dedicating energy and nutrients to growing larger ornaments rather than overall body size makes good evolutionary sense, Brown says.

Large ornaments are more effective at attracting females than a slight increase in body size. “It indicates that the male with the bigger trait had more resources,� he says.

Journal reference: Proceedings of the National Academy of Sciences (DOI: 10.1073/pnas.0602994103)

This validates the observation I’ve made that most women’s boobs grow waaaay way bigger as they gain weight, and that they seem to be the first to shrink when they diet.  Being a booty man, this doesn’t really phase me too much, but it’s sort of interesting that it’s now got a study to back it up.

On a related note:  how does one land a job staring at boobs all day?