Antlers and horns are usually associated with the male of the species, but sometimes the females bear battle armor.
Female dung beetles have horns that are used in challenging other female dung beetles for dung. Dung beetles lay their eggs in dung, and researchers have found that females with more robust horns produced more offspring than females of similar size but with smaller horns.
Experiments also showed that, unlike males, who may sport extravagant ornament to advertise their superior genetic makeup and suitability as a mate, female ornament does not play a role in sexual selection, at least among dung beetles. So it appears that development of showy weaponry in female dung beetles is related to survival in procuring resources, while in males it functions for survival of a different sort.
Sources: Millus, S., Female beetles ready for dung wars. Science News March 27, 2010
Watson, Nicola and Simmons, Leigh, Proceedings of the royal Society B, March 3, 2010
Watson and Simmons, Behavioral Ecology, March-April, 2010
Photo credit: Sean Stankowski
No comments:
Post a Comment