Evolution does not work that way. While natural selection does tend to favor beneficial traits in species, this does not mean that every single thing has evolved specificially with a purpose. Sometimes, weird shit pops up in biology that seems to serve no benefit to the species. That’s life.

The real problem with biology is that it is always assumed that humans are somehow unique to the point of superiority – for a long time, we were considered the only species with homosexual animals, the only species that had sex for pleasure, etc. The fact is, that if we enjoy having sex, then it’s no surprise that lots of other animals do it sometimes just for the pleasure (dolphins, etc).

Anyone who has ever masturbated can tell you how enjoyable it is and any decent sex therapist will tell you it’s perfectly normal. The only crime poor Ms. Elders committed was being ousted from politics by sexually-repressed religious imbeciles.

And goodness, can you imagine if most people could give themselves blowjobs? We’d never get anything done.

Female chimpanzees will actively rub their genitals with sticks. So, not only do they masturbate, they use sex toys.

Ever seen a female cat in heat, and what they manage to do with chair legs?

Is there actually any evidence to support female masturbation in other than the human species?

Shoot squirrels. One group after sex, one group after post coital masturbation and culture their urethras. Compare