/ polar bears

Polar Bears Experiencing Skin Lesions and Hair Loss

Published April 15, 2012 in Love For Earthlings, We Love Gaia, What's New |
Tags: , , , , , , ,

Nine Alaskan polar bears near the southern Beaufort Sea were found with skin lesions and hair loss in the past two weeks, according to the The United States Geological Survey (USGS). It is not known what is causing these conditions, but they could be man-made and natural biotoxins, radiation, contaminants, auto-immune diseases, nutritional, hormonal and environmental factors. The same problems were also observed in seals and walruses in the region.

According to a USGS memo,”Evidence of alopecia and other skin lesions may be difficult to see unless the bear can be observed closely. In the polar bears that USGS has observed to date,
the most common areas affected include the muzzle and face, eyes, ears and neck.”

In the southern Beaufort Sea region a USGS survey estimated there were about 1,526 polar bears. Because of climate change, there is less and less ice available for polar bears in this area. Offshore oil drilling began there in the early 1970s due to the presence of large oil and gas reservoirs.

Polar bears are vulnerable to man-made pollutants due to the fact wind currents carry them there from other places, so they can accumulate in large quantities. Polar bear bones have already been weakened by these pollutants.

Article by J. Richardson

Modern Polar Bears Orginated in Ireland

Published July 25, 2011 in Love For Earthlings |
Tags: , , , , , , , , , , , ,

Brown Bears and Polar Bears Met Often during Last 100,000 Years
A team of scientists discovered that the female ancestor to all modern polar bears was actually a species of brown bear living in Britain and Ireland just before the last ice age. The hybridization occurred between 20,000 and 50,000 years ago, and the species of brown bear has been extinct for the last 9,000 years.

According to the press release, “Beth Shapiro, the Shaffer Associate Professor of Biology at Penn State University and one of the team’s leaders, explained that climate changes affecting the North Atlantic ice sheet probably gave rise to periodic overlaps in bear habitats. These overlaps then led to hybridization, or interbreeding — an event that caused maternal DNA from brown bears to be introduced into polar bears.”

Researchers once thought that the female ancestor of polar bears lived about 14,000 years ago on the Alaskan islands of Admiralty, Baranof, and Chichagof. However, the new evidence collected from studying 242 brown bear and polar bear mitochondrial lineages (tracing genetic history from the mother’s side) from the last 120,000 years shows it happened tens of thousands of years earlier, and on a different part of the planet.

Hybridization Could Help Polar Bears Survive Environmental Changes
While polar bears and brown bears are strikingly different in their physical appearance, their ancestry seems to be intricately linked — and could be intermingled again as melting ice brings brown bears and polar bears back into contact with one another, creating hybrids of grizzlies and polar bears called “growler bears” or “pizzly bears.”

Apparently the hybridization we’ve witnessed recently due to global climate change and a reduction of sea ice has happened often over the last 100,000 years as warming and cooling cycles brought the bears in and out of contact with one another.

Shapiro states that a thorough understanding of the genetic history of polar bears as well as previous responses to environmental changes could conservationists form strategies for keeping polar bears from disappearing altogether.