The huge pandas we now know and love live on only the sidelines of special mountains in southwest China where they live only on bamboo. To support the hard and fibrous bamboo diet, they have distinct teeth, skulls and muscle features along with a special pseudo-thumb, the better to grab and hold bamboo stems, leaves and shoots. But according to new evidence reported in Contemporary biology January 31 was extinct, and ancient pandas were most likely a rich and complex diet.
"It is widely acknowledged that giant pandas have fed exclusively bamboo for the last two million years," says Fuwen Wei of the Chinese Academy of Sciences. But "our results showed the opposite."
It is impossible to know precisely what extinct animals ate. However, scientists can get traces by analyzing the composition of stable isotopes (various forms of the same element that contain the same number of protons but different numbers of neutrons) in animal teeth, hair and bones, including fossil moieties. In the new study, researchers first analyzed bone collagen of modern pandas (1970-2000) and other mammals from the same mountains.
The stable isotopic composition of carbon and nitrogen from modern pandas and other modern samples of mammalian bones has revealed three obvious groups: carnivores, herbivores and giant pandas. Huge pandas were uniquely unique due to their habit of eating bamboo. Subsequently, Wei's team measured bone collagen isotopes from 12 ancient pandas gathered from seven archaeological sites in south and southwest China and compared them with the patterns they observed in modern giant pandas.
Comparison of data has shown that old and modern pandas are isotopically different from one another, suggesting differences in eating habits. There were also bigger differences among the ancient species of panda, suggesting that the niches they occupied were about three times wider than the modern panda. This means that ancient pandas most likely had a varied diet similar to other mammals that lived beside them. They were, say researchers, "probably not exclusive bamboo feeders."
Researchers suggest that pandas' eating habits have evolved in two phases. First of all, the pandas came from being meat eaters or lobsters to become dedicated flowering plants. Only later did they specialize in bamboo.
Scientists have said they would now like to know exactly when the pandas have moved into the specialized diet they have today. To find out, they plan to collect and study more pand samples from different historical times over the past 5000 years.
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