A boa constrictor in the U.K. recently surprised caretakers by giving birth to 14 babies, all without the presence of a mate. This seemingly miraculous event is actually a scientific phenomenon known as parthenogenesis, whereby females of certain species can reproduce asexually, without the need for male fertilization. This process, derived from Greek words meaning “virgin” and “birth,” is not unique to snakes; various plants, insects, amphibians, reptiles, birds, and fish species are also capable of parthenogenesis.
Instances of parthenogenesis have been recorded in nature, with examples including a stingray named Charlotte from a North Carolina aquarium, who passed away this week without ever delivering offspring. Although some creatures, such as certain wasps, crustaceans, and lizards, solely rely on parthenogenesis for reproduction, it is more common in captivity for other species.
Experts like Demian Chapman, leading the Sharks & Rays Conservation Research Program at the Mote Marine Laboratory & Aquarium in Florida, suggest that parthenogenesis typically occurs when females are isolated from males. Recently, a Brazilian Rainbow Boa named Ronaldo residing at the City of Portsmouth College in the U.K. gave birth after being without contact with other snakes for over nine years.
In parthenogenesis, a female’s egg can fuse with another cell, often a remnant from the egg creation process, like a polar body, providing genetic material that would typically come from a male’s sperm. This fusion initiates cell division, ultimately forming an embryo. The prevalence of parthenogenesis in the wild remains uncertain, but instances have been reported among smalltooth sawfish in Florida’s coastal waters.
Offspring born through parthenogenesis tend to have reduced genetic diversity, potentially leading to developmental issues, as noted by Chapman. He emphasizes that the size of litters born through parthenogenesis is typically smaller than sexually reproduced ones, and anomalies in development may arise in some individuals from parthenogenetic births.
