New York, Jan 5 (IANS): Looking at parthenogenesis, or virgin birth, in snakes, researchers have discovered that facultative parthenogenesis, or asexual reproduction in an otherwise sexually reproducing species, appears to be quite common among snakes.

The findings may represent a potentially important feature of vertebrate evolution.

On the other hand, obligate parthogenesis - when organisms exclusively reproduce through asexual means - is extremely rare in snakes, the study showed.

Having recently been documented in natural populations and across a variety of lineages within the snake phylogeny, ranging from the boas and pythons through to the water snakes and pitvipers, the researchers revisited previous studies identifying commonalities and variations that offer new insight into this remarkable trait within snakes.

"Once considered a evolutionary novelty, facultative parthenogenesis has now been documented in an increasing number of vertebrate species, ranging from the hammerhead shark to domestic turkeys, komodo dragons to snakes; however it is this last group that offers us the greatest insight into this unusual reproductive trait," said study co-author Warren Booth from University of Tulsa in the US.

While researchers' understanding of these reproductive phenomena is in its infancy, the review provides the necessary first steps for investigating the origin and evolution of parthenogenesis in snakes.

The study appeared in the Biological Journal of the Linnean Society.