Adultery good for women too

It's always been accepted as fact that males (not just humans) always have had a great pressure to go forth and "colonize" as many females as possible. This obviously creates strain in monogamous relationships, but it also means that the male gets as many descendants as evolutionary possible. Turns out females going around sleeping with other males also provide them with benefits. From The Economist.com:

...modern genetic techniques have shown that in many species females in apparently monogamous relationships often produce families that have more than one father. To explain this, biologists have theorized that these females are mating with males who are genetically superior to their regular mates, thus getting the benefit of parental assistance from a cuckold and good genes from a Lothario.

I guess the whole "throw the first stone he/she who is without sin" readily applies here...