did these birds exist since prehistoric days?
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where did the polar bear live with her family In the Arctic Circle, encompassing the Arctic Ocean what do they eat? ringed and bearded seals are they very strict about their diet? No. in what way? They consume a wide variety of other wild foods, including muskox birds, eggs, rodents, crabs, other crustaceans and other polar bears.
wiki:25639076
Polar bear [SEP] Dietary flexibility
Although seal predation is the primary and an indispensable way of life for most polar bears, when alternatives are present they are quite flexible. Polar bears consume a wide variety of other wild foods, including muskox ("Ovibos moschatus"), reindeer ("Rangifer tarandus"), birds, eggs, rodents, crabs, other crustaceans and other polar bears. They may also eat plants, including berries, roots, and kelp; however, none of these have been a significant part of their diet, except for beachcast marine mammal carcasses. Given the change in climate, with ice breaking up in areas such as the Hudson Bay earlier than it used to, polar bears are exploiting food resources such as snow geese and eggs, and plants such as lyme grass in increased quantities.