A team of entomologists and reptile specialists from Virginia Polytechnic Institute and State University, the Chiricahua Desert Museum, the Illinois Natural History Survey, Reptilandia Reptile Lagoon and Parque Reptilandia has documented a case of a virgin crocodile laying viable eggs. In their paper published in the journal Biology Letters, the group describes their surprise at the discovery of a clutch of eggs laid by an American crocodile who had been kept alone in an enclosure at Parque Reptilandia park in Costa Rica for 16 years prior to laying the eggs.
