The first case of a crocodile who made herself pregnant has been identified at a zoo in Costa Rica. She produced a foetus that was 99.9% genetically identical to herself. The phenomenon of so-called “virgin birth” has been found in species of birds, fish and other reptiles, but never before in crocodiles.
The scientists say the trait might be inherited from an evolutionary ancestor. The research has been published in the Royal Society journal, Biology Letters. The egg was laid by an 18-year-old female American crocodile in Parque Reptilania in January 2018. The foetus inside was fully formed but stillborn and so did not hatch.
The crocodile who laid the egg was obtained when she was two years old and was kept apart from other crocodiles for its entire life. The park’s scientific team contacted Belfast-born Dr Warren Booth, who has been studying virgin births, known scientifically as parthenogenesis, for 11 years.
Dr Booth analysed the foetus and found that it was more than 99.9 % genetically identical to its mother – confirming that it had no father.