March 17, 2006â€”In biology, two heads are rarely better than one. But this unusual golden coin turtle, found in China, appears to be doing just fine. A businessman from the city of Qingdao says he bought the reptile at an animal market last year.
According to press reports released Wednesday, the turtle’s two heads cooperate well and can even eat at the same time. Its owner says the reptile eats more than one-headed turtles do and has grown over the past year.
The creature most likely developed its unusual anatomy while still in the egg. Its embryo began to split in twoâ€”the process that gives rise to identical twinsâ€”but then failed to fully separate.
While uncommon, abnormalities caused by incompletely split embryos occur in many animal species, including fish, snakes, rats, cowsâ€”even humans, where the phenomenon leads to what are known as Siamese, or conjoined, twins.
Experts say survival rates for two-headed animals tend to be lower in the wild. But in captivity such animals can prosper. At the San Diego Zoo a two-headed corn snake named Thelma and Louise produced 15 normal offspring before it died.
Photograph by ChinaFotoPress/Getty Images
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