An aquarium in Louisiana has made headlines with the birth of a baby shark, particularly after the egg hatched without the assistance of any male sharks.
Named Yoko, after the Chumash word ‘onyoko, which means “shark,” the swell shark pup was born in early January, according to the Shreveport Aquarium, CNN reported. It was hatched from an egg in a tank with two female sharks but no males.
The aquarium stressed that it had been more than three years since either of the sharks that could have laid the egg had interacted with a male. They theorized, however, that even in the absence of male sharks in the enclosure, the egg may have generated a pup in two ways.
First, scientists proposed that it could be created by parthenogenesis, a type of asexual reproduction in which the embryo develops from an egg without fertilization, according to the aquarium.
They also hypothesized that delayed fertilization, in which fertilization happens a long time after mating, might have occurred.
The Pritzker Laboratory for Molecular Systematics and Evolution’s manager, Kevin Feldheim, whose work focuses on shark population biology and mating behavior, told the outlet that parthenogenesis has been observed in several shark species, including the white-spotted bamboo shark and zebra shark. It is also thought to have happened in one species of ray.
Feldheim said that although there are instances of females giving birth in this manner even when males have been present, parthenogenesis typically occurs when females are separated from males.
Feldheim mentioned, “How parthenogenesis kicks in or what cues the females…to begin the process remains to be discovered,” adding that “in general, we think that this is a last-ditch effort by the female to pass on her genes. It speaks to how adaptable sharks are in terms of their reproduction.”
When Yoko is old enough, Shreveport Aquarium plans to test its genetic makeup to find out exactly how it was created.
Meanwhile, Yoko is under constant observation to guarantee its health and welfare.
“This situation is incredible and shows the resilience of this species,” Greg Barrick, the aquarium’s curator of live animals, said in a press release. “We are very excited in the coming months to confirm whether this was indeed a case of parthenogenesis or if it was delayed fertilization. It really proves that life… finds a way.”