Editing Long-tailed weasel (section)

==Evolution==
[[File:Frenataermineanivalis.png|left|thumb|Skulls of a long-tailed weasel (top), a stoat (bottom left) and [[least weasel]] (bottom right), as illustrated in [[Clinton Hart Merriam|Merriam]]'s ''Synopsis of the Weasels of North America'']]
The long-tailed weasel is the product of a process begun 5–7 million years ago, when northern forests were replaced by open grassland, thus prompting an explosive evolution of small, burrowing rodents. The long-tailed weasel's ancestors were larger than the current form, and underwent a reduction in size to exploit the new food source. The long-tailed weasel arose in North America 2 million years ago, shortly before the [[stoat]] evolved as its mirror image in [[Eurasia]]. The species thrived during the [[Last Glacial Period|Ice Age]], as its small size and long body allowed it to easily operate beneath snow, as well as hunt in burrows. The evolution of an elongated body shape maximizes the efficiency with which ''Mustela frenata'' can trap prey underground, as the majority of it lives in burrows and in tunnels.<ref name=":3">Frey, Jennifer K. ''Wild Carnivores of New Mexico''. Accessed April 24, 2025.</ref> The long-tailed weasel and the stoat remained separated until half a million years ago, when falling [[sea level]]s exposed the [[Bering land bridge]], thus allowing the stoat to cross into North America. However, unlike the latter species, the long-tailed weasel never crossed the land bridge, and did not spread into Eurasia.<ref name="mac205">{{Harvnb|Macdonald|1992|p=205}}</ref>

[[File:WEASEL.JPG|left|thumb|upright|Long-tailed weasel]]