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A first-ever recorded crocodile “virgin birth” has taken place in Costa Rica after a female made herself pregnant. Despite being kept in captivity in a zoo without contact with males, a fully-formed foetus was found inside one of her eggs.
The foetus’ genetic makeup was 99.9% identical to the mother, verifying that it had no father.
While virgin births, or parthenogenesis, have been recorded in birds, lizards, snakes and fish, it is the first time it has been documented in crocodiles.
The crocodile laid her clutch of eggs in 2018, when she was 18-years-old.
Seven of the eggs were incubated after appearing to be viable, but when none of them hatched after three months they were opened, with one containing a stillborn crocodile foetus.
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Virginia Tech researchers specialising in parthenogenesis studied the foetus and their findings were published in the Royal Society Journal Biology Letters.
They wrote that the discovery indicates virgin births may be happening among crocodiles without anyone previously noticing.
"It is not uncommon for captive reptiles to lay clutches of eggs, given the period of isolation from mates, these would normally be considered non-viable and discarded.
"These findings therefore suggest that eggs should be assessed for potential viability when males are absent.
"Furthermore, given that (virgin births) can occur in the presence of potential mates, instances of this may be missed when reproduction occurs in females co-habited with males."
According to the scientists the discovery offers “tantalising insights” into the potential reproductive capabilities of extinct relatives of crocodiles, most fascinatingly dinosaurs.