`The world of marine biology is scratching its collective head after a female shark gave birth to a pup even though it had apparently been nowhere near a male of the species.
The bonnethead shark has been swimming in a tank at the Henry Doorly Zoo in Omaha, Nebraska, US, with two female companions for the past three years. [..]
The pregnancy could be a case of parthenogenesis – or asexual reproduction – which, although common in some amphibians, has never been reported before in sharks.
More likely, say the zoo’s scientists, the shark was impregnated before she came to the center and retained a male’s sperm in her reproductive tract until she was mature enough to conceive.’