Fatherless pregnancies are more common in nature than previously thought, raising the question of whether humans could one day reproduce without men. Parthenogenesis, or virgin birth, has been observed in species such as lizards and sharks, where females can produce offspring without male genetic material. However, experts say the biological and evolutionary barriers for humans remain significant.
In theory, scientists could create sperm from female stem cells, allowing two women to conceive a child. Japanese researchers achieved this in mice a decade ago, producing a healthy offspring named Kaguya from two mothers. Yet Dr Allan Pacey, a reproductive biologist at the University of Sheffield, warns that replicating this in humans is a major challenge. 'We can make something that looks like a sperm cell under a microscope, but whether it is genetically programmed correctly is difficult to establish,' he says.
Even if such techniques were perfected, a woman reproducing entirely alone would face severe genetic risks. Self-fertilisation would reduce genetic diversity by half in each generation, increasing the likelihood of inherited disorders. Dr Pacey compares this to the genetic bottlenecks seen in European royal families, where conditions like the Habsburg lip—a pronounced jaw deformity—persisted due to inbreeding. 'It's not a good road to go down,' he adds. 'You would only really want to do this for one generation or two.'
In nature, parthenogenesis is typically a last resort for animals isolated from males, such as komodo dragons or sharks in captivity. While it offers a short-term solution, the loss of genetic diversity makes it evolutionarily disadvantageous for most large animals. For humans, the practical and ethical hurdles mean that men are unlikely to become obsolete anytime soon.
