What is the black footed ferret related to?

Answer 1

The Black-footed Ferret (Mustela nigripes) is a small carnivorous North American mammal in the family Mustelidae which includes weasels, mink, polecats, martens, otters, and badgers and is closely related to the Steppe Polecat of Russia.

Answer 2

That is unknown and controversial:

Within the genus Mustela, ferrets belong to the subgenus Putorius, from which there are only three extant species: M. putorius, the European polecat; M. eversmanni, the Siberian, or steppe polecat; and M. nigripes, the black-footed ferret. The European polecat lives in open forests and meadows, and is thought to be the ancestor of the domestic ferret. The Siberian or steppe polecat looks nearly identical to the black-footed ferret and leads a similar life on open grasslands and semi desert regions across Russia, China and Siberia.

Ferrets probably evolved in Europe, between three and four million years ago, from weasel-like ancestors. The earliest known ferret species, M. stromeri, probably gave rise to M. putorius and M. eversmanni during the middle Pleistocene. Ferrets dispersed from Siberia into North America during the late Pleistocene across the Bering land bridge, and advanced southeastward to the Great Plains through ice-free passageways. Over thousands of years of co-evolution with prairie dogs as prey, their behavior and biology gradually changed to suit their environment, and thus, they evolved into today's black-footed ferret. Although the first occurrence of black-footed ferrets is uncertain, scientists speculate that the species has probably been present in North America for at least 100,000 years. Molecular data collected from black-footed ferret specimens indicates that this species diverged from its Siberian counterpart between 0.5 and 2 million years ago.

source: http://www.blackfootedferret.org/facts-history.html

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