WASHINGTON, EU., June 2. 2015.- For many species, reproduction is derived from the male-female duet, but now researchers found evidence of “virgin births” in a vertebrate, sawfish, normally reproduce sexually.
However, seven sawfish in Florida are the first animals born to a female “virgin” an even environmentalists considered unusual situation that genetic diversity study say that such births may be more common than previously thought.
According to an analysis, it is estimated that nearly 4% of sawfish in an estuary of Florida was born without any genetic contribution from a male, a phenomenon known as parthenogenesis .
This asexual reproduction is rare in vertebrates and previously found only in a handful of species in captivity, including wild snakes and Komodo dragons.
The sawfish is a of the five species of large stripes have appendages resembling a chainsaw protruding from his face, and in the same subclass as sharks.
Previously, sawfish plentiful along the coast this and southern North Carolina to Texas, but overfishing and development has drastically reduced them to put them in danger, and now only found in southwest Florida.
The researchers obtained evidence of such 190 births sawfish while driving routine genetic testing to verify inbreeding, a Florida estuary.
Some of the fish analyzed showed unusually high levels-so relationship with others in the same population ties that are measured on a scale from zero to one, where the first indicates no link and 0.5 suggests that parents are brothers.
Seven of the 190 fish had values close to one relationship, the which means “virgin birth,” the researchers wrote in a paper published in the journal Current Biology.
Andrew Fields, first author of the study and fish geneticist at the University of Stony Brook, NY York, says his team initially doubted the findings but careful analysis ruled out other explanations than parthenogenesis.
“If perhaps an individual would not be a strong case, but the fact that we have so many in 190 samples, is pretty compelling, “he says.
The seven offspring are multiple layers and normal for their age, indicating that the offspring produced in this way can survive in nature.
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