16 Years At Home To The Zoo Without Hawking, This Female Crocodile Is Able To Lay

Illustration of crocodiles. (Unsplash/Maren Pauly)

JAKARTA - A group of scientists documented the events of the first known "virtual birth" in a crocodile, despite a 16-year isolated life in the Costa Rica zoo, according to a study.

American female crocodiles lay eggs 14 times in 2018 in their cages, an unusual phenomenon that occurs in reptiles in captivity.

However, more puzzling facts emerged after three months of incubation, when one egg was found to contain a perfect baby crocodile.

According to a study published in the journal 'Biology Letters', scientists tested the genetic makeup of the crocodile fetus. They found a DNA sequence showing the fetus was the result of a fatulative partenogenesis (FP), or reproduction without a genetic contribution from a male.

The FP phenomenon, which some scientists refer to as the "born of a virgin", was previously found in other species of fish, birds, lizards, and snakes. Scientists say this is the first known example in crocodiles.

In the FP, female eggs can develop into babies without being seeded by male sperm cells.

In making eggs, precursor cells divide into four cells. One becomes an egg and maintains the main cellular structure and cytoplasma such as gels, while the other stores additional genetic material.

Then, one of these cells basically acts as a sperm cell and blends with the egg to become "obtained".

American crocodiles are considered vulnerable and at risk of extinction in the wild. According to a hypothesis, FP may be more common in species that are on the verge of extinction, the study said.

Scientists say "the birth of a virgin" in Costa Rica could provide new information about the crocodile's ancestors who lived on earth in the Triassic Period about 250 million years ago.

"These findings offer tantalizing insight into the possible reproductive abilities of the extinct relatives of the crocodiles and birds, especially members of Pterosauria and Dinosaurs," the study said.