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Originally Posted by Minhrau
raccoon là giòng họ chồn chứ gấu mà có đuôi hả
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Nhìn thì giống chồn hơn giống gấu ...nhưng họ nghiên cứu và cho là :
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Based on fossil evidence from France and Germany, the first known members of the family Procyonidae lived in Europe in the late Oligocene about 25 million years ago.[20] Similar tooth and skull structures suggest procyonids and weasels share a common ancestor, but molecular analysis indicates a closer relationship between raccoons and bears.[21] After the then-existing species crossed the Bering Strait at least six million years later in the early Miocene, the center of its distribution was probably in Central America.[22] Coatis (Nasua and Nasuella) and raccoons (Procyon) have been considered to share common descent from a species in the genus Paranasua present between 5.2 and 6.0 million years ago.[23] This assumption, based on morphological comparisons of fossils, conflicts with a 2006 genetic analysis which indicates raccoons are more closely related to ringtails.[24] Unlike other procyonids, such as the crab-eating raccoon (Procyon cancrivorus), the ancestors of the common raccoon left tropical and subtropical areas and migrated farther north about 2.5 million years ago, in a migration that has been confirmed by the discovery of fossils in the Great Plains dating back to the middle of the Pliocene.[25] Its most recent ancestor was likely Procyon rexroadensis, a large Blancan raccoon from the Rexroad Formation characterized by its narrow back teeth and large lower jaw.[26]
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