Looking at the sawfish, you’ve got to wonder how males and females of the unusual species manage to have sex at all without bloodshed, amputations or at least some impressive contortions. Surprisingly they’ve been able to reproduce for eons but that alone has not been enough to keep them from becoming critically endangered. Now it appears one subspecies, the smalltooth sawfish (Pristis pectinata), may have figure out a miraculous way to save itself – the virgin birth.
Sawfish once cut through the waters of the Atlantic from North Carolina past Florida to Brazil, with some making the turn into the Gulf of Mexico to Texas. While not a commercial or game fish, many are accidentally snagged by their snouts in nets. Add that to development and collector cutting off their prized sawtoothed rostrums and it’s no surprise their numbers have been reduced by 95 percent to critically endangered levels.
That’s where the virgin births may help. According to a report in the current edition of the journal Current Biology, researchers at New York’s Stony Brook University found seven sawfish living in the Caloosahatchee and Peace rivers in Florida that were born to females without the benefit of sex or male sperm – a process called parthenogenesis. While it’s known that invertebrates such as insects and crabs can reproduce asexually and some birds, lizards and sharks have done it in captivity, this is the first recorded evidence of a vertebrate virgin birth in the wild.
Will this save the smalltooth sawfish? It can’t hurt. Five of the fish discovered were siblings, so the process has been going on for a while since virgin births generally occur one at a time. The researchers believe this is definitely a survival tactic. But how are they doing it?
The researchers will now look for DNA clues to determine why these female sawfish had virgin births and whether this may actually be a common occurrence among the species that just hasn’t been noticed before. They will also track the fish to see if they live as long as those born via conception. While virgin births may help stave off the extinction of sawtooths in the short-term, it’s not the solution, says researcher Kevin Feldheim of the Pritzker Laboratory in Chicago:
This should serve as a wake-up call that we need serious global efforts to save these animals.
It’s time to respond to some of these wake-up calls instead of hitting the snooze alarm.