Editing Muskrat (section)

== Description ==
[[File:Ondatra zibethica skeleton.png|thumb|left|Muskrat skeleton]]
[[File:Ondatra zibethica 02 MWNH 873.jpg|thumb|left|Muskrat skull]]
An adult muskrat is about {{convert|40|-|70|cm|in|0|abbr=on}} long, half of that length being the tail, and weighs {{convert|0.6|-|2|kg|lb|frac=4|abbr=on}}.<ref name="Burnie">{{cite book|editor-last1=Burnie |editor-first1=David |editor-last2=Wilson|editor-first2=Don E.|editor-link2=Don E. Wilson|year=2005 |title=Animal: The Definitive Visual Guide to the World's Wildlife |place=New York|publisher=DK Adult |isbn=0-7894-7764-5|lccn=2006272650}}{{page needed|date=September 2021}}</ref> That is about four times the weight of the [[brown rat]] (''Rattus norvegicus''), though an adult muskrat is only slightly longer. It is almost certainly{{clarify|date=November 2020}} the most prominent and heaviest member of the diverse family [[Cricetidae]], which includes all [[vole]]s, [[lemming]]s, and most [[Mouse|mice]] native to the Americas, and [[hamsters]] in Eurasia. The muskrat is much smaller than a [[beaver]] (''Castor canadensis''), with which they often share a habitat.<ref name="caras" /><ref name="nowak" />

Muskrats are covered with short, thick fur, which is medium to dark brown or black, with the belly a bit lighter ([[Countershading|countershaded]]); as the animal ages, it turns partly gray. The fur has two layers, which protect it from cold water. They have long tails covered with scales rather than hair. To aid in swimming, their tails are slightly flattened vertically,<ref>{{cite web|url=http://m.extension.illinois.edu/wildlife/directory_show.cfm?species=muskrat |title=Wildlife Directory: Muskrat |website=Living with Wildlife in Illinois |publisher=University of Illinois Extension|access-date=2012-12-20|archive-url=https://web.archive.org/web/20110518043248/http://m.extension.illinois.edu/wildlife/directory_show.cfm?species=muskrat|archive-date=2011-05-18|url-status=dead}}</ref> a shape that is unique to them.<ref>{{cite web|last=Lavender|first=Catherine |url=http://www.library.csi.cuny.edu/dept/history/lavender/muskrat.html |title=Late Winter on Staten Island: The Crepuscular Dance of the Muskrats|website=Staten Island Through the Seasons |publisher=College of Staten Island |access-date=2012-12-20|archive-url=https://web.archive.org/web/20120204075059/http://www.library.csi.cuny.edu/dept/history/lavender/muskrat.html |archive-date=2012-02-04 |url-status=dead}}</ref> When they walk on land, their tails drag on the ground, which makes their tracks easy to recognize.<ref name="caras" /><ref name="nowak" />

Muskrats spend most of their time in water and are well suited to their semiaquatic life. They can swim underwater for 12 to 17 minutes. Their bodies, like those of [[Earless seal|seals]] and [[whale]]s, are less sensitive to the buildup of [[carbon dioxide]] than those of most other mammals. They can close off their ears to keep water out. Their hind feet are partially webbed<ref>{{cite web|url=https://www.ndow.org/species/muskrat|title=Muskrat|website=Nevada Department of Wildlife|year=2024|access-date=27 November 2024}}</ref> and are their primary means of propulsion. Their tail functions as a rudder, controlling the direction they swim.<ref>{{cite journal |last=Fish|first=Frank E.|year=1982|title=Function of the compressed tail of surface swimming muskrats (Ondatra zibethicus)|journal=Journal of Mammalogy|volume=63|issue=4|pages=591–597|doi=10.2307/1380263|jstor=1380263}}</ref>