Wild Female Snakes Give Virgin Births

A new study has detected virgin births by female snakes living in the wild.

A team of researchers studied two closely related species of North American pit vipers - the copperhead from Connecticut and the cottonmouth snakes from Georgia. They found that the female snakes belonging to either of the two species were capable of giving birth to offspring on their own without any help from the males.

The females were found to be reproducing using a method known as facultative parthenogenesis, wherein an egg laid by the female grows without getting fertilized by the male sperms.

While asexual reproduction has been documented among invertebrates, it is still been considered a rare process among vertebrates with very few species like a captive shark and a captive giant lizard being reported as asexual. This is the first time that virgin births have been recorded in wild female snakes.

When the researchers monitored the two species of snakes, they did not separate the females from males but allowed them to interact with them. They collected the pregnant snakes of both the species from the wild and gathered the specimens of the litters. 

They performed DNA analysis and found two litters among the 59 litters were virgin births. Despite interaction with the males, the female snakes were able to reproduce through facultative parthenogenesis. This suggested that isolation from males does not really play a significant role in females' asexual reproduction, reported LiveScience.

Researchers involved in the study were astounded to find the discovery.  "I think the frequency is what really shocked us," lead author Warren Booth, from the University of Tulsa in Oklahoma, told LiveScience.

He added saying,"In the copperhead population, we detected one instance in 22 litters, whereas in the cottonmouths, it was one in 37 litters. Essentially, somewhere between 2.5 and 5 percent of litters produced in these populations may be resulting from parthenogenesis. That's quite remarkable for something that has been considered an evolutionary novelty, even by me up until this finding."

Researchers are still unclear as to what causes the snakes to reproduce using the facultative parthenogenesis, but believe that it could shed light on another evolutionary process.

While studies on captive virgin births have shown that offspring were not able to survive and reproduce, it is not known if the virgin births of wild snakes will be able to reproduce and give birth to virgin or normal births, reported BBC.

But the researchers clearly pointed out that virgin births are not possible among mammals, except for platypus and echidnas, as mammals need a process known as genomic imprinting, wherein a set of genes from the mother and another set of genes from the father interact with each other to develop an embryo, the BBC report said.

The findings of the study are published in the journal of RoyalSociety Biology Letters.