A female crocodile has made herself pregnant, in what scientists have called the first-known case of a “virgin birth” in the species

A female crocodile has made herself pregnant, in what scientists have called the first-known case of a “virgin birth” in the species.

The crocodile, who is from a zoo in Costa Rica, has not come into contact with a male crocodile in nearly 16 years.

According to research published in the scientific journal Biology Letters, the crocodile was able to produce an egg with a fetus that was 99.9% genetically identical to herself.

Such virgin births have been seen before in species of birds, fish and other reptiles. However, the phenomenon was never before seen in crocodiles.

The researchers say the crocodile may have inherited the ability from an evolutionary ancestor, which suggests that dinosaurs may also have been capable of asexual reproduction. The crocodile, who is an 18-year-old American crocodile, lived in captivity in Parque Reptilania.

She laid the egg in January 2018. The fetus inside the egg was fully formed but did not hatch, as it was stillborn. Dr Warren Booth, who analysed the fetus, told BBC News that the discovery was not surprising.

“We see it in sharks, birds, snakes and lizards and it is remarkably common and widespread,” he says. He says the reason such births were not observed in crocodiles before was because there were no efforts to detect them.

“There was a big increase in reports of parthenogenesis when people started keeping pet snakes. But your average reptile keeper doesn’t keep a crocodile.”