A researcher has discovered six male sharks pregnant off the coast in eastern India, reports Science News. Marine biologist Alissa Barnes noticed there were male bigeye houndsharks than females, yet the males had a 'visible stomach bulge'. Alissa Barnes reported during a session at the 5th International Marine Conservation Congress on June 25. In her published report, Barnes called this phenomenon 'intersexuality'.
Barnes dissected the fish and found the 'male sharks' had external claspers - like most male houndsharks - but they also had ovaries like their female counterparts. Another shark biologist told Science News that hermaphroditism - an organism containing both male and female reproductive systems - is rare in sharks.
In her report, Barnes wrote, "Externally, these specimens appeared to be immature males that had visible stomach bulge." The bulge turned out to be shark pups in six of the seven cases, she said, adding that all the males had penises and 'fully developed female sex organs'.
Barnes told Science News that anomaly might be caused by 'pollutants in the water' or 'hormonal changes'. She wrote that there is a growing need to understand this phenomenon and its underlying causes. Experts tell a male from a female shark by the sperm-delivering claspers on their underside which is like a penis.