Captive shark had ‘virgin birth’:
The birth of the hammerhead (of the bonnethead species, Sphyrna tiburo) at Henry Doorly was as tragic as it was puzzling.The new pup was soon killed by a stingray before keepers could remove it from its tank.
At the time, some theorised that a male tiger shark kept at the zoo could have been the father — but the institution’s three bonnethead females had none of the bite marks that are usually inflicted on their gender during shark sex.
Some even suggested that one of the females could have had sex in the wild and stored the sperm in her body — but the three-year period in captivity made this explanation highly unlikely.
The new tests on the dead pup’s tissues now show the newborn’s DNA only matched up with one of the females — and there was none of any male origin.
Although extremely rare in vertebrates, parthenogenesis (out of the Greek for “virgin birth”) occurs in a number of lower animals. Insects such as bees and ants use it to produce their drones, for example.