beavers evolution
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Evolution of the Beaver


beaversketchingssmallOrigins seem to show the beaver or castoridae first evolved in north America and later spread to Eurasia. Other genera of the species existed. One giant size died out ten thousand years ago. It would have been the size of a black bear and weighed 500 pounds. The beaver is a member of the rodent family. Its closest relation is the squirrel, sharing a similar leg bone design. Muskrats and nutrias are more distant cousins even though their habits are similar. Today two species - castor canadensis north American beaver and castor fiber, the European beaver, survive.beaveryoungsmall Before the 1800's the beaver would have had many sub species, some living west of the rockies, on islands in the Atlantic and Pacific costal areas. These would have evolved a little more differently than the beaver in larger wetland locations in forested regions of Canada. After the beaver was almost wiped out in the 1900's, mixing of the breeds took place and today all beavers look very much the same right across the continent. Colors and size may vary a little depending where they live, the further south generally they smaller they are with lighter fur.



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