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To the surprise of scientists, a species of endangered fish in Florida has found a way to reproduce without sex and produce successful virgin births. Smalltooth sawfish (Pristis pectinata) are large fish with sawlike snouts that are related to sharks, and due to overfishing and coastal habitat loss, are now critically endangered and found in only a handful of locations in southern Florida. 

A study of the fish in one such area astounded scientists when DNA fingerprinting showed that approximately 3% of the population were the result of “virgin births”, making this is the first solid evidence of such asexual reproduction in the wild for any vertebrate. 

Asexual reproduction (also known as parthenogenesis) is often seen among invertebrates but happens rarely in vertebrates, and has been reliably observed more frequently in captive animals of a range of species. In those instances, the animals in question surprised their keepers by giving birth despite the fact that they'd had no male partners around with which to mate, but until now, no one really knew if this phenomenon took place to any significant extent in the wild. 

Since virgin birth is essentially an extreme form of inbreeding, scientists thought of vertebrate parthenogenesis as a curiosity that doesn’t usually lead to viable offspring. And yet the fish the researchers found in Florida appeared to be in perfect health. It appears then, that the phenomenon may be more common in wild populations than we ever thought. 

Rare species in particular, like those that are endangered or colonizing a new habitat, may be the ones that are doing it most often, and for smalltooth sawfish, it's possible this ability could keep them going for a little longer. But it’s clear that without urgent human intervention, it still won't be enough to save them.