If a species is separated by any means causing a barrier between them they cannot mate with each other causing reproductive isolation, because of the reproductive isolation, natural selection will occur and the species will begin to change. Noting this can take thousand or maybe millions of years. Looking up the example of the polar bear recent studies suggest that polar bears split from a common brown bears 350,000 – 6 million years ago, undergoing a series of evolutionary changes in order to survive in the Arctic. (Polar Bears International,…
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 relation this event.…
Polar bears are extreamly well adapted tohunt their prey under water. Keeping warm is no problem for polar bears infact sometimes polar bears have to lay flat on their stomachs on the ice just to cool of. Polar bears have the thickest fur of any bear species. Their fur has two layers. The first layer, the under coat, is the closest to their body it consists of thick, plush, hair that retains heat. The next layer, the outer layer, is a layer made of "guard hairs" and are not actually hair at all they are hollow tubes. the tubes trap air for insulation andalso reflect a visible wavelengths of light in their hollow air space, which combine to make the fur whiteeven though it is in fact colorless. The white coloring provides camoflauge for the bears allowing them to blend in with there white snowy surroundings. Under their fur polar bears have black skin that absorb the sunlight and under that they have a 4-inch layer of blubber. This blubber keeps polar bears warm in the cold water. Polar bears have fur at he bottom of their feet providing extra warmth and traction to the ice. they are adapted to swim 60 miles without a pause to rest. They have have the ability to reduce their metabolic rate when the food is scarce and again when it's…
Even without annual and seasonal variation, discrimination of foods can occur between sexes. Larger males rely more on animal protein to sustain their large body mass, whereas females can persist on vegetative diets alone. ( Munro, R. H., Nielsen, S. E., Price, M. H., Stenhouse, G. B., & Boyce, M. S. 2006). In this study, we will take a sample of Grizzly bears and test to see if the food they choose depends on the sex of the bear or if the time of year effects the food preferred. Since the diet of the Grizzly bear is ever-changing the food sources available also encounter growths and declines as well. Once the majority of the Grizzlies diet was Cuttthroat Salmon, however since the predation on the salmon was so high for a great length of time in the Grizzlies' diet and forced the Salmon numbers to decline dramatically the Grizzly diet has switched. New evidence suggests that the decline of native cutthroat trout has caused omnivorous grizzly bears to kill more elk calves in some areas. (Middleton, A. D., Morrison, T. A., Fortin, J. K., Robbins, C. T., Proffitt, K. M., White, P. J.,…
The purpose of this memo is to explain the causes of extinction within the Red wolf population and the Black bear population. The topics chosen explain how this issue came about, what factors created, and provided some solutions on how to prevent it and keep these endangered species’ population thriving. There were several ways the black bear and red wolf came to the brink of extinction and these article provide multiple solutions to sustain and endangered species.…
The Department of the Interior protects America’s natural resources while honoring our various heritage, cultures, and tribal communities as well as supplies the energy of the future. The primary focus is within the Fish and Wildlife Service of the Federal Government. The existence of wildlife and plants is constantly threatened as a direct result of humanity. Global Warming is finally receiving acknowledgement necessary to make a difference in the wasteful and destructive routines of human expansion. Artic wildlife is experiencing the most difficulties as the surrounding glaciers are all melting. Our primary focus is on polar bears as they rely on masses of ice to rest after hunting for food. With the emergence of warmer climate, the areas of ice are diminishing leaving polar bears swimming for even longer until they drown from exhaustion. A federal regulation was passed in May of 2008 to protect the polar bear species from extinction by adding them to the endangered list. This should be a wake-up call to every individual living on the planet Earth as it is time to take responsibility for our actions and start making serious changes. Continued decrease of sea ice levels is expected in the future which affects the entire span of polar bears which reclassifies their status as threatened and endangered.…
Polar bears and brown bears are genetically closely related. This is evident from similarity of both species DNA and their their structure. Another indication of the close relationship between polar bears and brown bears is the fact that they can interbreed and produce crossbreed offspring. (poler bears and brown bears).…
The most recent change was the molar teeth. With this change the polar bear now has forty-two teeth that are much longer and larger than the regular brown bear which have flat rounded teeth. The interbreeding of grizzle bears and polar bears has created a new type of bear. Polar bears and grizzly bears are breading at an increased frequency due to global warming, which is slowly forcing the polar bears out their natural environment. This cross breading has been increasing as more brown bears have been spotted in polar bear territory and parts of Canada, the traits of this new hybrid bear consist of long dirty white fur, long claws, wider teeth, and a slightly larger head. In addition, this new hybrid demonstrates more similar behavior to polar bears than grizzle…
The human impact on today’s enlivenment for polar bears isn’t the best. Polar bears are finding harder to service with ice melting earlier in the spring and refreezing later in the fall. With larger oil companies moving closer into the arctic it is affecting the bears even more. Already having to deal with clement change and ice melting faster, big oil has moved in and poring toxins in to the environment. With the working of the oil rigs, oil is spilling out into the water poising the polar bears food sources. Other sea life is ingesting the oil then the polar bear eats the food and then is poising themselves. Polar bears with low health are not able to mate and have cubs, if the bears do have cubs the cubs die at an early age do to the lack…
Medical assistants perform administrative and clinical tasks to keep the offices of physicians, podiatrist, chiropractors, and other health practitioners running smoothly. The duties of medical assistants depend on the location and size of the practice and the practitioner's specialty. In small practices, medical assistants usually do many different kinds of tasks, handling both administrative and clinical duties and reporting directly to an office manager, physician, or other health practitioner. Those in large practices tend to specialize in a particular area, under the supervision of department administrators. “Administrative” medical assistants update and file patients' medical records, fill out insurance forms, and arrange for hospital admissions and laboratory services. They also perform tasks less specific to medical settings, such as answering telephones, greeting patients, handling correspondence, scheduling appointments, and handling billing and bookkeeping.…
Parks Canada provides an estimate of 20,000 Grizzly bears in Canada (regions included: British Columbia, Western Alberta, the Yukon and North Western Territories) (2014). But, a recent study by Sawaya et al. (2012) has suggested that Grizzly Population is already in decline in some parts of Canada such as Banff National Park and the numbers presented by Government of Canada are lower than the reality. Furthermore, The Committee on the Status of Endangered Wildlife in Canada cites them as species of special concern (2012). Amid all this, conflicts with humans can make this situation even worse as they can induce human caused mortality of Grizzly bears. Stakeholders have taken actions and measures to address the issue of Human – Grizzly bear conflict; however, no compelling results have been seen so far. Some actions such as aversive conditioning and hunting ends up hurting the population further; thus, contradicting the inherent nature of both conservation biology and animal welfare science. It is evident that Grizzly bear – Human conflict causes significant harm to the animals, and actions taken to resolve this issue are proving to be ineffective. Therefore, for successful results a paradigm shift must be undertaken to focus on conservation and welfare equally.…
Researchers found evidence of rapidly melting ice where walruses feed. The development of the ice is significant because walruses use sea ice as a resting platform, for pups and their mothers (Butler). If walruses cannot adapt to caring for their young without sea ice the population will plummet. In order for seals to cope with global warming, they need to shift their territories to suitable ice conditions (Ringed Seals and Climate Change). Seals desire to breed is altered by warmer temperature. The seals are not having as much offspring because the average pup survival rate is…
neither would lose a fight with any other land carnivore, including the great cats. The Alaskan brown bear and the polar bear share similarities and…
Birds. Some animals get disease from they eat and drink. An antibiotic was discovered in the soils of the threatened New Jersey Pine Barrens Natural Area. Significant impact of global warming is already discernible in animal and plant populations. The synergism of rapid temperature rise and other stresses, in particular habitat destruction, could easily disrupt the connectedness among species and lead to a reformulation of species communities, reflecting differential changes in species, and to numerous extirpations and possibly extinctions. Global warming is quickly becoming the biggest threat to the long-term survival of America’s wildlife. Average temperatures in the U.S. over the last century have already increased by more than one degree Fahrenheit. Seven of the top 10 warmest years on record for the contiguous 48 states have occurred since 1998, and 2012 was the warmest year on record. Without significant new steps to reduce carbon pollution, our planet will warm by 7 to 11 degrees Fahrenheit by the end of the century, with devastating consequences for wildlife. In the western U.S., warming and drought stress are causing trees to die and making them more vulnerable to pine beetle and other insect infestations. Higher temperatures and increased fuel from dead trees have led to more wildfires. Global warming can lead to mass species extinction. Some scientists predict as many as a third of all species will become extinct by 2050. Goble warming mess up the food chain. It cost many play to die off of drought. Polar bears rely heavily on Arctic sea ice, which is rapidly disappearing due to global warming. Climate change is altering key habitat elements that are critical to wildlife's survival and putting natural resources in jeopardy. Many scientists believe the rate of climate change is too rapid for various species to keep up. The gas is considered by many scientists to be responsible for global warming and has consistently breached the mark for a…
According to Brian Schwimmer, “kinship is constructed from a set of categories, groups, relationships, and behaviors based upon culturally determined beliefs and values concerning human biology and reproduction.” (Schwimmer, 1996) This definition resonates with me because it has the influx of the sociobiology and relativist perspective on the subject. Faubion describes kinship as “…illustrative of the constitution of intersubjectivity, of organized alterity…” (Faubion, 2001) which can be defined as a method of illustrating and identifying those related to oneself. Faubion argues that it is human nature that influences this common “…mode of organizing alterity that appears to rest on a biological definite ground from which it nevertheless tends to float free…” (Faubion, 2001) Despite the tension, in which Faubion describes as the differentiating between natural and invented kinship relations, there is a common framework as to how humans classify their kin.…