A critically endangered species of sawfish has been observed reproducing through parthenogenesis, a process of “virgin birth” that biologists have previously believed incapable of producing viable offspring.
According to researchers at New York’s Stony Brook University, smalltooth sawfish have been observed asexually reproducing, something that they assert has never before been viably documented in vertebrate animals. The population of sawfish was discovered in an estuary in Florida, according to the Huffington Post, and approximately 3 percent of the animals were determined to be the product of virgin births.
— Mysterious Universe (@mysteriousuniv) June 1, 2015
In Florida, the sawfish that were determined to come from virgin births are living in harmony with the rest of the population, which were conceived through normal means. That fact has astonished researchers, who say that while parthenogenesis isn’t rare in the animal kingdom, viable offspring from the births are. Snakes, insects, fish, and lizards have all been known to give birth spontaneously, particularly when in captivity, but usually the offspring are unfit, according to Andrew Fields, the Ph.D. candidate responsible for the study.
“The fact that we are seeing these survive in the wild is a big step. As far as we can tell… there was no outward sign of them not behaving as the other ones that we saw.”
— david todd (@aquafiles) June 1, 2015
Relatives of sharks, sawfish are a critically endangered group of fish, thanks to habitat degradation and overfishing. The sawfish can reach lengths of up to 25 feet, as the Inquisitr previously reported, and are characterized by a toothy snout used to disable prey. Once found through much of the Atlantic, the sawfish now chiefly inhabit a handful of locations near Florida, as Yahoo News reports.
— SlashGear (@slashgear) June 1, 2015
The study involved 190 sawfish, which were subjected to DNA sampling between 2004 and 2013. Of those animals, seven were found to be the product of virgin births, confirmed by their genetic material.
“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,” Fields detailed. “What the DNA fingerprints told us was altogether more surprising – female sawfish are sometimes reproducing without even mating.”
While the findings, which were detailed June 1 in the journal Current Biology, are set to rewrite textbooks, the research team cautions that parthenogenesis represents an extreme form of inbreeding, even when successfully carried out. They assert that the virgin births alone will not be enough to save the endangered sawfish.
[Photo by Forest Samuels CC BY-NC-SA 2.0 via U.S Fish and Wildlife Services]