TIGER shark embryos cannibalise their siblings in the womb in a pre-birth battle for paternity, new research has revealed.
The American and South African study studied genetic samples from 15 pregnant female sharks which had died after being caught in shark nets off the coast of South Africa.
The study published in Biology Letters showed 10 of the sharks carried just two embryos, while the other five, in an earlier stage of pregnancy, had between five and seven embryos in utero.
Using DNA analysis to determine the paternity of the embryos, the larger litters had at least two fathers, while the litters with only two sharks more often had just one father.
Study co-author Professor Demian Chapman, a marine biologist at Stony Brook University of New York, said that proved one embryo - possibly the one that grew biggest first - tended to devour embryos from other fathers.
The study concluded the practice was an evolutionary strategy allowing the most aggressive male sharks to father the surviving embryos, and thus outdo their sexual rivals.
"It's exactly the same sort of DNA testing that you might see on Maury Povich to figure out how many dads there are," Chapman told LiveScience, referring to the American TV talk show host.
"And basically, that loser father ultimately provided food for a rival male."
It has been known since the 1980s that shark foetuses cannibalised each other in utero - with one scientific legend relating how a shark embryo bit a researcher's hand during a dissection - but scientists hadn't known why.
Anda sedang membaca artikel tentang
Paternity battle in the belly of sharks
Dengan url
http://suarabisikan.blogspot.com/2013/05/paternity-battle-in-belly-of-sharks.html
Anda boleh menyebar luaskannya atau mengcopy paste-nya
Paternity battle in the belly of sharks
namun jangan lupa untuk meletakkan link
Paternity battle in the belly of sharks
sebagai sumbernya
0 komentar:
Posting Komentar