Bad news, guys

From an AP story in the Boston Globe (Female sharks don't need males to reproduce, study finds)

Female sharks can fertilize their own eggs and give birth without sperm from males, according to a new study of the asexual reproduction of a hammerhead in a US zoo... Analysis of the baby shark's DNA found no trace of any chromosomal contribution from a male partner. Shark specialists said this was the first confirmed case in a shark of parthenogenesis, a word derived from Greek that means "virgin birth."...Before the study, many shark specialists had presumed that the Nebraska birth involved a female shark's well-documented ability to store sperm for a lengthy period of time...The lack of any paternal DNA in the baby shark ruled out this possibility.

It's the first documented example of asexual reproduction in mammals. Watch out, fellas, our days may be numbered.