Evolutionary studies suggest that polar bears evolved from brown bears during the ice ages. The oldest polar bear fossil, a jaw bone found in Svalbard, is dated at about 110,000 to 130,000 years old. DNA comparisons suggest the species may have split at least 150,000 years ago, and maybe longer.
How did brown bears turn into polar bears?
The polar bear has evolved over time from the common brown bear by changing its fur colour to white, the ideal colour to blend in with its ice-covered surroundings. With new data an international research team now documents that the separation from the brown bear into an independent species has gone very quickly.
When did polar bears separate from brown bears?
Polar bears diverged from brown bears surprisingly recently—within the past 500,000 years, researchers report today in Cell. Previous studies suggested that the separation occurred between 600,000 and 5 million years ago.
How did brown bears become white?
Some 200,000 years ago, when glaciers covered much of Eurasia, the Arctic Ocean was completely frozen. It was during this challenging period that brown bears began to wander in search of food. … The bears also grew white fur, which camouflaged them in their snow-covered surroundings and gave them a hunting advantage.
What is the ancestor of the polar bear?
However, analysis of mitochondrial DNA – which is passed from mother to child – has shown the extinct Irish brown bears are the ancestors of all today’s polar bears, the scientists said. Their work provides evidence of the two species mating opportunistically during the past 100,000 years or more.
How did the bear evolve?
Bears are the youngest of the carnivore families, having arisen from doglike ancestors during the Eocene Epoch 55 million to 38 million years ago. The earliest bears had the characteristics of both dogs and bears, with heavy-set features and blunter teeth than those of true dogs.
How did polar bear evolve?
Evolutionary studies suggest that polar bears evolved from brown bears during the ice ages. … The timing of when polar bears first appeared as a species is important because it will determine when they experienced warm periods with little sea ice in the past, and help assess their response to current changes in sea ice.
When did humans discover polar bears?
Constantine John Phipps was the first to describe the polar bear as a distinct species in 1774 in his report about his 1773 expedition towards the North Pole. He chose the scientific name Ursus maritimus, the Latin for ‘maritime bear’, due to the animal’s native habitat.
What animals did bears evolve from?
The evolution of bears as we know them today, started around 30 million years ago. Their ancestors evolved into a family of small mammals known as the Miacids (Miacidae). The bears, small bears and also the canines developed from the Miacids.
Why polar bears are white?
1. Why do polar bears have white fur? Polar bears have white fur so that they can camouflage into their environment. Their coat is so well camouflaged in Arctic environments that it can sometimes pass as a snow drift.
What eats a polar bear?
Adult polar bears have no natural predators except other polar bears. Cubs less than one year old sometimes are prey to wolves and other carnivores. Newborn cubs may be cannibalized by malnourished mothers or adult male polar bears.
Who is stronger polar bear or grizzly bear?
A grizzly bear is likely able to beat both a polar bear and a black bear in a battle for survival.
What is the real color of a polar bear?
Although while polar bears usually look white, their fur isn’t white at all. And their skin is black! Polar bear fur is actually see-through, but it takes on a white color because of its structure. Your hair gets its color from something called pigment.