Eurasian Beaver - Differences From North American Beaver

Differences From North American Beaver

Although the Eurasian beaver appears superficially similar to the North American beaver, there are several important differences between the two species.

Aside from being the larger of the two species, the Eurasian beaver has the following anatomical differences to North American beaver: it has a larger, less rounded head; a longer, narrower muzzle; a narrower, less oval-shaped tail; shorter shin bones, making it less capable of bipedal locomotion than the North American species. The Eurasian beaver also has longer nasal bones, with the widest point being at the end of the snout; in the case of the North American beaver, the widest point is at the middle of the snout. The Eurasian beaver has a triangular nasal opening, unlike those of the North American beavers, which are square. Furthermore, the foramen magnum is rounded in the Eurasian beaver, but triangular in the North American beaver. The anal glands of the Eurasian beaver are larger, and thin-walled, with a large internal volume, relative to that of the North American beaver. The guard hairs of the Eurasian beaver have longer hollow medullas at their tips. There is also a difference in fur colour: overall, 66% of Eurasian beavers have beige or pale brown fur, 20% have reddish brown, nearly 8% are brown, and only 4% have blackish coats; in North American beavers, 50% have pale brown fur, 25% are reddish brown, 20% are brown, and 6% are blackish.

The two species are not genetically compatible. The North American beaver has 40 chromosomes, while the Eurasian beaver has 48. After more than 27 attempts, made in Russia, to hybridize the two species, the result was one stillborn kit from bred from the pairing of a male North American beaver and a female Eurasian beaver. The aforementioned factor makes interspecific breeding unlikely in areas where the two species' ranges overlap.

Read more about this topic:  Eurasian Beaver

Famous quotes containing the words differences, north, american and/or beaver:

    What strikes many twin researchers now is not how much identical twins are alike, but rather how different they are, given the same genetic makeup....Multiples don’t walk around in lockstep, talking in unison, thinking identical thoughts. The bond for normal twins, whether they are identical or fraternal, is based on how they, as individuals who are keenly aware of the differences between them, learn to relate to one another.
    Pamela Patrick Novotny (20th century)

    I am fearful when I see people substituting fear for reason.
    —Edmund H. North (1911–1990)

    Our security depends on the Allied Powers winning against aggressors. The Axis Powers intend to destroy democracy, it is anathema to them. We cannot provide that aid if the public are against it; therefore, it is our responsibility to persuade the public that aid to the victims of aggression is aid to American security. I expect the members of my administration to take every opportunity to speak to this issue wherever they are invited to address public forums in the weeks ahead.
    Franklin D. Roosevelt (1882–1945)

    This ferry was as busy as a beaver dam, and all the world seemed anxious to get across the Merrimack River at this particular point, waiting to get set over,—children with their two cents done up in paper, jail-birds broke lose and constable with warrant, travelers from distant lands to distant lands, men and women to whom the Merrimack River was a bar.
    Henry David Thoreau (1817–1862)