A team of researchers from Stony Brook University in New York (USA) has discovered several young comb sawfish ( Pristis pectinata ) that have been born without sexual reproduction , in a process called parthenogenesis in which it is not an essential requirement for the egg to be fertilized (since it absorbs a genetically identical cell). Although this form of reproduction can occur in crustaceans, insects or amphibians, it is the first time that it has been observed in a vertebrate born in the wild .
“We were genetically identifying this subspecies of sawfish to find out whether, due to their small population, individuals from the same family were reproducing with each other when we discovered that females sometimes reproduce without mating, ” explains Andrew Fields, co-author of the study.
Investigating this group of offspring found in Florida (USA) the experts found that about 3% of these fish had been born thanks to asexual reproduction (through parthenogenesis). This fact causes the offspring to have half the genetic diversity of their mothers and to die easily. What is unusual, in this case, is not only that the seven offspring of this subspecies at risk of extinction were born in the wild in this reproductive way, but that they were in perfect condition.
For experts, “this should serve as a wake-up call about the need for global efforts to save it,” says Kevin Feldheim, co-author of the study. And it is that the comb sawfish is in danger due to the loss of its coastal habitat and overfishing.
The study has been published in the journal Current Biology .





