The environmental pressure of the Pleistocene ice age caused a fast evolutionary jump from the species of Grizzly bears to Polar bears. The climate an animal lives in plays a large part in the composition of an animal. The availability of prey is one of the most crucial parts of survival. Mutations of species can impact them or die off quicklier. The composition of an animal is based highly off its habitat location. The Grizzly bear’s habitat before the ice age was in a deciduous forest. Grizzly bears had concave faces, a distinctive hump on their shoulders, and long claws about two to four inches long. Both the hump and the claws are traits associated with a grizzly bear’s exceptional digging ability. They were known for being able to …show more content…
The grizzly bear’s coat was brown. They could camouflage very easily with their surroundings in the wood. There were occasionally mutations in coat color and those bears would die off quicklier not being able to camouflage. Once the Pleistocene ice age came the environment was completely different, it was now artic. The occasional lighter mutations begain to survive easier and better than the darker colored bears because they were able to get closer to the seals without them seeing which meant they could catch them easier. The darker bears had difficulties now in this mostly snowy environment with camouflage. The seals would see them and swim away, because they weren’t eating as well they would die off easier. Over time the number of mutations began to grow. The mutations started reproducing making a lighter color coat in bears. This kept happening until the Polar bear evolved with a transparent coat. Polar bears hair looks white because the air spaces in the hairs scatter light of all colors. When something reflects all of the visible wavelengths of light, we see the color white. The Polar bear’s transparent coat helped them a lot with camouflage which helped them with
Now even though these bears help the environment so will other bears. The Grizzlies are just another species of the many species of bears why are these bears more important than other bears. As we find from the GNWT: “Grizzly Bears in the NWT occur primarily in open alpine or tundra habitats, but they can also be found in forested areas. They have large home ranges relative to most other bear species. On average, a male’s range can exte...
The one way to keep bears and humans safe and living in the same environment is learning to understand them and being able to tolerate them. If people don’t do these things theses beautiful animals will begin to decrease in numbers. While there are a lot of black bears in Alaska, an estimated 100,000, hunters believe that you can just hunt and hunt and the population will decrease to average, but the plans of some hunters seems just over the top of making these bears go on to the endangered species list. But with the help of people and cooperation the Black Bears will continue to live in Alaska.
Lamarck’s ideas on polar bear evolution Lamarckism can be used to explain the evolution of polar bears from brown bears, specifically skin and fur color. Lamarck’s theory stipulated that a characteristic (brown or white fur color) which is used more by an organism will become stronger. One that is not used disappears eventually. Change occurs when polar bears want to change. If a polar bear’s phenotype changes during life in order to adapt its environment, those changes are passed onto its offspring.
Bears can live anywhere but Grizzly bears live in subalpine meadows and dense forests. When grizzly bears hibernate they usually live in caves. A sloth of bears is usually a mom and the cubs. The mom bear is called a sow, the dad bear doesn't have a name because they are never with the family and the babies are called cubs. There is usually a dearth amount of cubs in a family. The families are always together and not with a different family. All bear look different but I'm not talking about the other bears I am talking about grizzly bears. Grizzly bears are usually just the color brown and not really anything different. Grizzlys need big paws to get around and travel. Bears have small black eyes. Their eyes are small because they don't need very good eyesight because they have such good sniffers. Usually the weight of a cub is about 4- 10 pounds when they are born but when they are adults they weigh 175- 500 pounds.
Although they are now rare, grizzly bears inhabit the dense forest of Montana’s Rocky Mountains. Grizzlies grow as tall as eight feet and can weigh up than 1,000 pounds, yet they can move as fast as a horse. There are six national grizzly recovery zones, and three are in Montana. They are Cabinet-Yaak, Northern Continental Divided, and Yellowstone (Av2 books).
Grizzly bears are enormous bears; that, tend to be misunderstood by others. Many times, they are portrayed wrongly in movies and tv shows. People may go off by things they see; in the movies and immediately suggest that’s the way the grizzly bear is. If others took the time to find information on the grizzly they would see how wrong the movies are about them. For many people grizzly bears can be a mystery such as where they live, what they eat, and whether they hibernate or not. However, with a bit of research answers can be found.
The Grizzly bear (Ursus arctos) has long been considered to be the symbol of the wild. They are beautiful, powerful and at the same time vulnerable animals. They are known to survive in remote areas not inhabited by humans. The Grizzly was once able to occupy most of the land from northern Mexico to Alaska and most places in between. With a disappearing natural habitat and one of the lowest reproduction rate of any mammal in North America the Grizzly bear has seen population number fall dramatically. Most Grizzly bears left in the continental United States are located in four states near Yellowstone National Park. Canada has Grizzly populations in five provinces. The state of Alaska has the largest population of these amazing animals. With change in habitat due to human involvement and low reproduction rates, Grizzly bears have had a hard time sustaining population numbers. This has caused them to virtually become non-existent in certain areas of North America and is forcing the bears that are left to move to more sufficient areas that can sustain their populations.
Evolution in general, is a hard concept to grasp. There are multiple factors that effect the outcome a species, for example: genetics, nurture, nature, and the environment all play an important role. It was once said that species do not survive due to the fact that they are the strongest or the most intelligent, but because that species is the most responsive to change.
To begin with, the melting of polar ice caps has caused polar bears to swim long distances. According to Bryan Walsh of TIME Magazine the melting of the ice caps have caused polar bears especially the young cubs to swim longer distances which has caused a “ forty-five percent mortality rate” (Walsh). In the article Walsh, writes about a study that showed that younger cubs because of low fat and strength were more likely to die due to the long di...
American Black Bears are covered with soft, long fur. Although they are called “Black Bears,” American Black Bears are not always black. They can range anywhere from a darker blonde color to jet-black. On the Western part of the United States, the Black Bears are normally a lighter color, whereas the Black Bears in the Center of the United States are darker. American Black Bears ar...
According to Darwin and his theory on evolution, organisms are presented with nature’s challenge of environmental change. Those that possess the characteristics of adapting to such challenges are successful in leaving their genes behind and ensuring that their lineage will continue. It is natural selection, where nature can perform tiny to mass sporadic experiments on its organisms, and the results can be interesting from extinction to significant changes within a species.
One huge impact of global warming is the change in animals’ habitats. When the earth’s temperature is increasing, it creates the change of weather conditions in a certain area, which causes some kinds of animals in this area to live with many difficulties, or sometimes those kinds of animals are forced to move to new region when they cannot handle the difficulties. The arctic fox is an example for this situation. According to the article “How Does Global Warming Affect Wildlife,” arctic foxes prefer to live in the cooler environment while their habitat is getting warmer and warmer due to global warming, so arctic foxes have to leave their own home to seek a more suitable area (National W...
cinnamon, or even blonde in color. Black bears are not usually aggressive, and often escape
A polar bear is a one of the eight species. “Scientists believe that the polar bear began over 200,000 years ago. They came from the brown bears ancestors.” Most experts think that polar bears are the longest bears. Males measure over 10 feet long, when standing on their hind legs, other bear not so much. Brown bears and polar bear are the largest and are both land carnivores. Polar bears are one of the worlds largest world predictors.
As glacial ice receded and the climate warmed up, the fauna changed as some animals began to become more scarce, such as fewer mammoth herds for example. The warmer climate brought new sources of meat that had become more readily available over time. Reindeer became a main source of hide, bone, antler, and of course meat.