The Sawfish Virgin Births

Sawfish Virgin Birth

A young sawfish

We normally associate a virgin birth with religious matter, but forget Bethlehem, the magical waters of Florida appear to be really working miracles with sawfish virgin births.

The smalltooth sawfish is critically endangered but observations suggest that the offspring are appearing without any males involved in mating – this animal behaviour has never been observed in nature before.

Not enough males

The author of the paper which reported the finding was Andrew Fields, who explained, “with fragmented habitat and low abundance,” the fish are finding it difficult to find mating partners which seems to have triggered less than usual births amongst certain adult females.

Small incidence

The research team from Stony Brook University’s School of Marine and Atmospheric Science, were performing some DNA profiling of the sawfish and discovered 3% of the fish studied were subjects of the virgin birth. This process is known by scientists as parthenogenesis.


It is thought that this occurred when an unfertilised egg absorbs a genetically identical sister cell. The result of this process is normally that the offspring have half the genetic mix of the mothers and frequently die. However, observations of the virgin birthed fish have determined they are in great health.

The offspring have been tagged for further investigation but the scientists believe that they may give birth either with or without the input of a male.

More than sawfish

The sawfish are a form of Ray, which is related to Sharks, and it is thought that this phenomenon may well be more common than we think across the various species. Evidence of this has sometimes come from management of aquariums where the staff have sometimes been surprised by the appearance of baby sharks without any male input.

It is possible that more species will join the virgin birth list soon, but don’t put your money just yet on it being humans.