Changes

[[Image:Polar_bears.jpg|left|thumb|200px|A mother polar bear and her two cubs]]

[[Image:Polar_bears.jpg|left|thumb|200px|A mother polar bear and her two cubs]]

The current world population is estimated at around 22-27,000, around twice what it was in the 1960s.<ref>http://www.naturecanada.ca/climate_change_polar.asp</ref> Nonetheless, environmentalists got the polar bear placed on the [[Endangered Species List]] "to force the U.S. government to take action on [[global warming]]. <ref>The aim of the environmentalists is to use the Endangered Species Act to force the U.S. government to take action on global warming, said Kassie Siegel, a lawyer for the [[Center for Biological Diversity]]. It would require federal agencies "to look at the cumulative effect of greenhouse gases on polar bears" and limit emissions by cars and power plants, Siegel said. [http://www.usatoday.com/weather/climate/globalwarming/2008-03-09-polar-bears_N.htm] </ref>]

The current world population is estimated at around 22-27,000, around twice what it was in the 1960s.<ref>http://www.naturecanada.ca/climate_change_polar.asp</ref> Nonetheless, environmentalists got the polar bear placed on the [[Endangered Species List]] "to force the U.S. government to take action on [[global warming]]. <ref>The aim of the environmentalists is to use the Endangered Species Act to force the U.S. government to take action on global warming, said Kassie Siegel, a lawyer for the [[Center for Biological Diversity]]. It would require federal agencies "to look at the cumulative effect of greenhouse gases on polar bears" and limit emissions by cars and power plants, Siegel said. [http://www.usatoday.com/weather/climate/globalwarming/2008-03-09-polar-bears_N.htm] </ref>

Polar bears have been known to [[interbreed]] with [[grizzly bear]]s in the wild, producing a polar-grizzly hybrid.<ref>http://www.msnbc.msn.com/id/12738644/GT1/8199/</ref>

Polar bears have been known to [[interbreed]] with [[grizzly bear]]s in the wild, producing a polar-grizzly hybrid.<ref>http://www.msnbc.msn.com/id/12738644/GT1/8199/</ref>