Washington, Jan 27 (Inditop.com) Shark pups born to virgin mothers can survive long-term, says new research. Genetic analysis confirmed the first known case of a virgin female shark producing multiple offspring that survived.
Two daughters of the white-spotted bamboo shark are now more than five years old. Earlier research proved that reproduction occurred in two other shark species sans male sperm, called parthenogenesis, but the offspring did not survive in those cases.
“Parthenogenesis may not be as much of a dead-end mode of reproduction as we thought for these sharks,” said Demian Chapman, Institute for Ocean Conservation Science at Stony Brook University, who co-authored the study.
Kevin Feldheim, manager of the Pritzker Laboratory for Molecular Systematics and Evolution at the Field Museum, analysed the sharks’ genetic material to rule out any paternal reproduction assistance.
“Examination of highly variable sections of the genome prove that these young sharks had no father,” Feldheim said.
“The findings are remarkable because they tell us that some female sharks can produce litters of offspring without ever having mated with a male,” he added.
“We compared several sections of the genome between two of the young sharks and their mother. It turned out that all the genetic material in each of the young ones came from the mother, proving there was no father,” Feldheim said.
Although the shark mother was kept in a tank at the Belle Isle Aquarium in Detroit, where only another female of a different but related species resided, genetic testing ruled out the possibility of its encountering male sperm earlier in life.
A second analysis using more general techniques to examine more than a 100 additional regions of the genome was performed by Sean Fitzpatrick, doctoral student and Paulo Prod�hl, head of the Fish Genetics and Molecular Ecology Laboratory, of Queen’s University in Belfast, to confirm Feldheim’s finding.
Young sharks didn’t share all their mother’s genetic material and aren’t true clones of her, but more like “half-clones,” said Feldheim, according to a Stony Brook release.
The findings were published in the Journal of Heredity.
