While a virgin birth sounds like a rare event, experts on parthenogenesis said Charlotte has performed a miracle of life far more common than most people understand. Dozens of species — zebra sharks, California condors and Komodo dragons — can reproduce asexually through parthenogenesis.

The phenomenon has been observed in every class of animals, except for mammals, which have a mechanism that prevents parthenogenesis.  

The common form of parthenogenesis happens during meiosis, when gametes (the cells that create new organisms in sexual reproduction) are created. When eggs are produced, byproducts are created called polar bodies, which contain genetic information. 

During spontaneous parthenogenesis, eggs fuse with polar bodies to create a new offspring without the genetic contribution of another parent.