Mountain Beaver
Overview
The Mountain Beaver is the most primitive extant rodent
Rodent
Rodentia is an order of mammals also known as rodents, characterised by two continuously growing incisors in the upper and lower jaws which must be kept short by gnawing....

. Not to be confused with the North American beaver Castor canadensis, or its relative the Eurasian beaver, Castor fiber, it has several common names including Aplodontia, Boomer, Ground Bear, and Giant Mole. The name Sewellel Beaver comes from sewellel or suwellel, the Chinookan
Chinookan
Chinook refers to several native amercain groups of in the Pacific Northwest region of the United States, speaking the Chinookan languages. In the early 19th century, the Chinookan-speaking peoples lived along the lower and middle Columbia River in present-day Oregon and Washington...

 term for a cloak made from its pelts.
 
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