‘Virgin Shark Birth' in Italy: Baby Common Smooth-Hound Shark Born to Single Mother in First Documented Case of Parthenogenesis, Know All About It
In a groundbreaking discovery, Italian researchers have documented the first case of parthenogenesis, or "virgin birth," in the endangered common smooth-hound shark (Mustelus mustelus).
Mumbai, August 1: In a groundbreaking discovery, Italian researchers have documented the first case of parthenogenesis, or "virgin birth," in the endangered common smooth-hound shark (Mustelus mustelus). The findings, published in a journal, highlight a significant phenomenon in a species threatened by illegal fishing in the Mediterranean and other warm waters.
The study, conducted by the Experimental Zooprophylactic Institute of Piedmont, Liguria, and the Aosta Valley and published in Scientific Reports, observed two female M mustelus sharks in captivity at the Cala Gonone Aquarium in Sardinia. These sharks, both 18 years old and in captivity since 2010, have exhibited parthenogenesis annually since 2020. This process allows a female to reproduce asexually without the need for sperm to fertilize the egg. Rainbow Boa Snake 'Ronaldo' Gives Birth to 14 Snakes! Reptile Thought to be Male Delivers Snakelets in England's Portsmouth in Rare Virgin Birth; What Does Parthenogenesis in Snakes Mean?
"Remarkably, this finding reveals that parthenogenesis can occur annually in these sharks, alternating between two females, and conclusively excludes long-term sperm storage as a cause," the study's authors noted.
What is Parthenogenesis?
Parthenogenesis, more common in invertebrates than in vertebrates, has not been observed in mammals. However, it is known to occur in reptiles and some species of sharks, rays, and skates, allowing them to adapt their reproductive strategies to environmental conditions. The researchers suggest that a reduction in the male population could be a pivotal factor driving this phenomenon. Virgin Crocodile Gets Pregnant in Costa Rica Zoo: Crocodile Found to Have Made Herself Pregnant, Scientist Study Rare Case of 'Virgin Birth'.
The study tracked the two female sharks for 13 years in the absence of males, yet observed nearly annual production of young. DNA analysis of the offspring confirmed that they were not conceived through long-term sperm storage. While studying parthenogenesis in wild sharks poses challenges, captivity conditions provide an ideal environment for long-term monitoring. Similar cases have been documented in other shark species in aquariums in the United States, the United Arab Emirates, and Australia over the past two decades.
The common smooth-hound shark, a midsize species found in shallower waters, can live up to 25 years but is classified as endangered. Population estimates suggest a potential decline by half in the coming decades. Currently, only one of the sharks born through parthenogenesis at the aquarium remains alive, while the two adult females continue to thrive in their large exhibition tank alongside other Mediterranean marine species.
(The above story first appeared on LatestLY on Aug 01, 2024 09:19 PM IST. For more news and updates on politics, world, sports, entertainment and lifestyle, log on to our website latestly.com).