Female Polar Bears

The Polar Bear (Ursus maritimus) is a bear native largely within the Arctic Circle encircling the Arctic Ocean, its surrounding seas and land masses. Although it is closely related to the Brown Bear, it has evolved to occupy a narrower ecological forte, with many body characteristics adapted for cold temperatures, for moving across snow, ice, and open water, and for hunting the seals which make up most of its diet. Though there are many theories surrounding evolution, the two stand outstanding hypotheses applying to the modification from Brown Bear to Polar Bear are Lamarck’s theory of Use and Disuse, and Darwin’s theory of Natural Selection. The intention of this paper is to compare these thesis and determine the most appropriate in

One Child Policy Imagine not having control of the amount of kids you have. Mao Zedong was a communist leader. In 1949 Mao wanted more people in China. Later in 1960 he contradicted himself and believed bigger families were better for China. Thirty million people died and that caused Mao to change his mind.

They need food, water, shelter, and a safe place to live. Depending on where they live they sometimes travel along a coast line which is a good place to find food. When the weather gets cold they return to their winter home, which they migrate to year after year. They return to their territory where they were born during the cold season to hibernate. Their hunting ground is their territory they sometimes share their territory with smaller animals and tend to go back to there hunting grounds year around; if they lose their hunting grounds to another bear they must find a new one. Polar bears hunt ring seals during the spring and early summer. They also eat wild berries, seaweed, and grass when they come across them. They will also go after snow geese, lemmings, birds’ eggs, dead whales, and walruses. They can get a successful kill every five days. (Smith)

There are not many creatures in the world that have the ability to not only survive thirty-two degrees below zero temperatures, but live in this climate as well. Among penguins and seals, polar bears are apart of the group of creatures that live everyday life in these freezing conditions. However, polar bears were not always able to do this. According to the Public Broadcast Service (PBS) website, polar bears evolved from brown bears through microevolution. Microevolution, by definition, is “small-scale evolution that occurs from one generation to the next” (Larsen p. A15). Due to the discovery of fossils, it is believed that brown bears evolved into polar bears between 70,000 to 100,000 years ago. This evolution can be seen by the change of fur color from brown to white to blend in while hunting for food and by the growth of a thicker, warmer coat to protect against the cold temperatures (PBS). This all occurred because of an event called the “ice age”. However, in the year 2316, an event called “global warming” will cause a much different evolution. Global warming is a phrase used to describe the ongoing, subtle rise in temperature of the earth and it’s oceans. Because of the small efforts being made to slow down global warming, nearly all of the ice caps in the ocean will most likely be melted by the year 2316. With polar bears only being able to survive by living on polar

The Polar Bear are found on the icy coasts that surrounds the North Poles and as far south as Hudson Bay. Around 60%of Polar Bears can be found in Canada with the remainings throughout Greenland, Alaska, Svalbard, and Russia where tend to be close to the ocean across the icy fields. The habitats are affected by human encroachment by hunting , and releasing chemical pollutants into the water.The Polar Bear eats Seals, Walrus, and Seabirds. Polar Bears can live up to 20-30 year. Polar Bears have a lot of fur and their fur is clear, white, or yellow. The Polar Bear is 6.5 ft-8.3ft. they can weigh up to 330lbs -1,322lbs and they can swim up to 25mph.

Climate change is one of the causes that have been effecting the polar bears survival. Climate change is caused by the greenhouse gases, which are human’s emissions in their every day life use. These emissions form an outer warm layer in the atmosphere that will keep the earth warmer than the normal all around the world. As the atmosphere gets surrounded by these emissions that makes it warmer the sea ice in the area where polar bears live starts to melt causing the endangerment of the polar bears. Polar bears rely on Sea ice for hunting seals one of their main prey becoming complicated to retrieve causing bears to suffer starvation for the lack of time to hunt the prey.

One way that also helps polar bears hunt is their appearance. When hunting for anything other than a seal, the bear will use its white coat to get closer to the prey. Polar bears have huge claws and strong jaws with one pointed row of teeth. Polar bears also have small hairs on the bottom of their feet so they can have more friction on ice. The few things we can see on a polar bear that is not white are their eyes, nose, claws, and, paws. As you can see, the appearance of a polar bear helps them survive.

Polar bears diets mainly rely on seals so the current changes in ice will affect the life cycle of the seals as well as it will play a big role in the life cycle of an adult polar bear. A large decrease in adult polar bears has been noticed and is believed to have been noticed and is believed to have been caused by the ice changes over the last few years as the decline in the seal population results in the polar bears being hungry during the winter which means they are not storing enough fat to produce energy to keep them alive all winter resulting in the polar bears unable to survive the cold winter months without their natural food source (Prowse et al,

Polars bears are top predators in the Arctic and are therefore exposed to high levels of pollutants through their food. The popular belief that polar bears live in a pure frozen wilderness is a fantasy.

Due to the effects of greenhouse gases, the sea ice that polar bears rely on for foraging and shelter is declining rapidly. Some populations of polar bears are forced to depend on their stored fat for energy during summer due to melting of the sea ice, which prevents them from hunting more efficiently. Being forced to rely on stored fat leads to a decline in energy intake, which leads to a decline in body mass. A decline in body mass correlates with slower reproductive rates and decreasing survival rates, which effects the growth and genetic diversity of the population. The increased amount of open water in between sea ice causes the polar bears to swim for greater lengths and therefore makes it more difficult for female polar bears to find proper dens for reproducing and protecting their offspring (Derocher and Stirling, 2012). The rate at which the sea ice declines is projected to accelerate over time (Derocher and Stirling, 2012), which means we will soon reach a year when severe malnutrition will lead to an irreversible decrease of polar bear populations (Aars et

The polar bear lives up in the Arctic region where global warming and climate change are melting the ice caps that the bears thrive on. They use the ice as a platform from hunting and rest. The random pocket holes in the ice, where the seals pop up at, is where the polar bear catches its prey. With this reduction of ice, “the abundance of seals, and increases the amount of energy and time needed for hunting, leaving less energy for reproduction” (Endangered Species and Habitats).

This report will mainly focus on the adaptations of the biggest carnivore on the planet---the adaptations of polar bears. Polar bears,

The reality, neither adopts a way of intrigue and nor urge for its approval. It is itself a great power.

Overpopulation continues to be the leading driver of hunger, desertification, species depletion, and a range of social problems across the planet. China is the world's most populous nation with around 1.357 billion people and India, with 1.252 billion, is catching up fast. Combined, the two nations share more than one-third of the world's population. Both of the countries are grappling with huge populations and the problems that arise with them, but they have chosen to employ drastically different ways of coping. The population of China has become managed as a result of the One Child Policy. Fifty years ago, China was the most populous country in the world, and while it still is, the population has not grown as much as it would have if the

Polar bears mostly live in the costal ice or north pole Because of thick clear fur that protects it body from the extreme temperatures of the snow and the ice cold water. The polar bear is a carnivore that eats’ seals, walrus, seabird but humans and global warming are killing them. The polar bear run across the ice or put it head in a hold to get food for it babies or for itself to eat. When they make babies they put them in hole and when they grow up they can live up to 20-30 years in their life. But most of them are gone because of environmental problems and global warming because of us humans doing bad things to the world. So the area threaten animal which causes them to might go extinct which is bad for the animal.