In an interesting role reversal that would win approval from Sadie Hawkins, female squinting bush brown butterflies or Bicyclus anynana, court males more actively when exposed to cool, dry temps, a study by Yale University researchers found recently.

Bicyclus Anynana

Bicyclus Anynana

The report was published in the January 7 issue of the journal Science.
The female African butterflies, when raised in conditions of 62 degrees Fahrenheit, were considerably more promiscuous than their less aggressive sisters raised at 80 degrees.
Even more intriguing, the more promiscuous females live longer lives than those engaged in “more passive mate shopping.”
The male butterflies deliver nutrients as well as sperm to the females during mating, said Kathleen L. Prudic, post-doctoral researcher in the department of ecology and evolutionary biology and co-author of the paper.   The double delivery appears to lead to increased female longevity. The females strive to survive the dry season, displaying their striking ornamental eye markings and coupling with as many males as possible in order to earn valuable male-only resources.

Monarchs mating

Butterflies mating in November 2010. Wonder if she pursued him?

The male butterflies, meanwhile, become extremely selective about who they choose to be the recipient of these precious gifts.  Why?
Because once they do, they die younger.

Read more about the study here.