Nature & Environment

Wild 'virgin-born' sawfish are a world first

By T.K. Randall
June 2, 2015 ·  8 comments

The sawfish have started reproducing asexually. Image Credit: CC BY 2.0 USFWS / Forrest Samuels Ecologists made the discovery while studying genetic diversity and believe that it is the first time ever that a species has been found to have reproduced asexually outside of captivity.

"We were conducting routine DNA fingerprinting of the sawfish found in this area in order to see if relatives were often reproducing with relatives due to their small population size," said study author Andrew Fields of Stony Brook University in New York.

"What the DNA fingerprints told us was altogether more surprising: female sawfish are sometimes reproducing without even mating."Out of 190 sawfish examined the researchers found 7 that had been the result of a virgin birth, something thought to have been made possible by a process known as 'parthenogenesis' which involves an unfertilized egg developing into an embryo after absorbing an identical sister cell.

While extremely rare, the phenomenon has been observed before in captive animals including vipers, turkeys, komodo dragons and even sharks.

In this case it appears to have occurred as a last-ditch evolutionary response to the fact that smalltooth sawfish numbers have dwindled to just 5% of what they were 100 years ago.

Source: BBC News | Comments (8)

Tags: Sawfish, Virgin Birth