12,000 years ago, the MOUNTAIN BEAVER called all of North America home,,,,,,,,,,,,,,,,,,Nicknamed the "LIVING FOSSIL", this Beaver is hypersensitive to warm temperatures and are subject to heat stroke and death if termperatures rise above 32 degress celsius......Their last stronghold are the mountains of Vancouver and British Columbia where in addition to global warming, logging and housing developments(dogs and cats attack and kill the beavers) threaten this species which dates back 25 million years ago

Mountain Beavers, Canada's elusive 'living fossil' can't take the heat

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The Mountain Beaver, Canada's "living fossil"

Although most residents there probably have never seen one before, the mountain slopes outside of Vancouver are home to the world's most primitive species of rodent. Being the last in a line dating back over 25 million years and having several physical characteristics that are only seen now in fossil specimens, has earned the Mountain Beaver the nickname 'Living Fossil'.

Also referred to as 'ground bears' and 'giant moles', the only thing they share with the North American Beaver is their name. Instead of building dams and lodges, they live in dens dug into the ground, and they only have short stubby tails, rather than the North American Beaver's distinctive wide, flat tail.Unfortunately, due to logging and urban expansion, their habitat is shrinking and rising temperatures due to climate are putting them in further danger.

Their exact numbers are unknown, however, a 1999 study that put them on the federal government's Species at Risk list found 634 occupied nests during their survey of southern BC, on the east side of the Cascade Mountains.

According to one of the authors, logging is the biggest threat to the mountain beaver, since the heavy equipment compacts the earth, making it difficult for them to dig their dens.Urban expansion takes its toll as well, by encroaching on the beaver's habitat and introducing dogs and cats into the area, which would see the docile animals as easy prey.

Also, being such a primitive species, these creatures have a hard time regulating their body temperatures, and are extremely sensitive to heat and drought. They begin to suffer from hyperthermia if the temperature rises above 28 degrees Celsius and can die if they're exposed to temperatures above 32 degrees Celsius for more than a few hours. They originally lived all across North America, but ended up in the cooler Pacific Northwest forests as the climate gradually warmed up from the last ice age.