© Warren BoothThis boa constrictor is the result of a "virgin birth" in which its mama reproduced without a male in a phenomenon called parthenogenesis.
For the first time, scientists have discovered a boa constrictor that reproduces by virgin birth.
Intriguingly, these giant female serpents only gave birth in this fatherless manner in years when males were present, researchers added.
Asexual reproduction is common among invertebrates (animals without backbones), and is rare in vertebrates, but not unknown. For instance, the
komodo dragon, the world's largest living lizard, has given birth via parthenogenesis, in which an unfertilized egg develops to maturity.
Scientists investigated a female boa constrictor at the Boa Store in Sneedville, Tenn., an online store that sells captive-bred boa constrictors. The female had given birth to litters of young this year and last. These offspring were all female and, unusually, were all caramel in color like their mother. This rare trait is recessive in nature, meaning it gets expressed only if offspring receive the DNA for it from both their parents, and none of the males that the female had been exposed to were known to carry the trait.
Genetic tests revealed that none of these litters carried any genes from any of the males their mother had known. The baby snakes must have been fatherless, the first time parthenogenesis has been seen in boas.
