Editing Mustelidae (section)

== Characteristics ==
[[File:Black-footed ferret skeleton.jpg|thumb|Skeleton of a [[black-footed ferret]] (''Mustela nigripes'') on display at the [[Museum of Osteology]]]]
Within a large range of variation, the mustelids exhibit some common characteristics. They are typically small animals with elongated bodies, short legs, short skulls, short, round ears, and thick fur.<ref>{{Cite journal|last1=Law|first1=C. J.|last2=Slater|first2=G. J.|last3=Mehta|first3=R. S.|title=Shared extremes by ectotherms and endotherms: Body elongation in mustelids is associated with small size and reduced limbs|journal= Evolution|issue=4|pages=735–749|doi= 10.1111/evo.13702|year=2019|volume=73|pmid=30793764|doi-access=free}}</ref> Mustelids' long, slender body structure is adapted to three main lifestyles: terrestrial, arboreal, and aquatic/semi-aquatic.<ref name=":0">{{Cite book |title=Biology and conservation of musteloids |date=2018 |publisher=Oxford University Press |isbn=978-0-19-182051-9 |editor-last=Macdonald |editor-first=David W. |edition=First |location=Oxford |editor-last2=Newman |editor-first2=Christopher |editor-last3=Harrington |editor-first3=L. A.}}</ref> They exhibit digitigrade or plantigrade locomotion, with five toes on each foot, enabling them to move in different ways (i.e. digging, climbing, swimming).<ref name=":1">{{Cite book |title=Mammalogy: adaptation, diversity, ecology |date=2020 |publisher=Johns Hopkins university press |isbn=978-1-4214-3652-4 |edition=5th |location=Baltimore, Maryland}}</ref> Most mustelids are solitary, nocturnal animals, and are active year-round.<ref name=EoM>{{cite book|editor-last=Macdonald |editor-first=D.|last= King |first=Carolyn|year= 1984|title= The Encyclopedia of Mammals|publisher= Facts on File|location= New York|pages= [https://archive.org/details/encyclopediaofma00mals_0/page/108 108–109]|isbn= 978-0-87196-871-5|url= https://archive.org/details/encyclopediaofma00mals_0/page/108}}</ref> Their dense fur, often serving as natural camouflage, undergoes seasonal changes to help them adjust to varying environmental conditions.<ref name=":0" />

With the exception of the sea otter<ref>{{cite book | title=The Sea Otter in the Eastern Pacific Ocean | last=Kenyon |first=Karl W.|
year=1969|publisher=U.S. Bureau of Sport Fisheries and Wildlife|location=Washington, D.C.|url=https://books.google.com/books?id=JKUeAQAAIAAJ}}</ref> they have [[anal scent gland]]s that produce a strong-smelling secretion the animals use for [[sexual signalling]] and [[marking territory]].

{{anchor|Reproduction}}
Mustelids exhibit sexual dimorphism, with males being larger than females, but degree varies between species as well as geographically within species.<ref name=":0" /> Male mustelids have a bifurcated penis and baculum.<ref name=":1" /> Most mustelid reproduction involves [[embryonic diapause]].<ref>Amstislavsky, Sergei, and Yulia Ternovskaya. "[https://web.archive.org/web/20171117174933/https://pdfs.semanticscholar.org/f3b8/69a6701e7bb11035119faf36745f0bd0fafc.pdf Reproduction in mustelids.]" Animal Reproduction Science 60 (2000): 571–581.</ref> The [[embryo]] does not immediately implant in the [[uterus]], but remains dormant for some time. No development takes place as long as the embryo remains unattached to the uterine lining. As a result, the normal gestation period is extended, sometimes up to a year. This allows the young to be born under favourable environmental conditions. Reproduction has a large energy cost, so it is to a female's benefit to have available food and mild weather. The young are more likely to survive if birth occurs after previous offspring have been [[wean]]ed.

Mustelids are predominantly carnivorous, although some eat vegetable matter at times. While not all mustelids share an identical [[dentition]], they all possess teeth adapted for eating flesh, including the presence of shearing [[carnassial]]s. One characteristic trait is a meat-shearing upper-back molar that is rotated 90°, towards the inside of the mouth.<ref>{{cite web | last = Pratt | first = Philip | title = Dentition of the Wolverine | publisher = The Wolverine Foundation, Inc. | url = http://www.wolverinefoundation.org/dentition.htm | archive-url = https://web.archive.org/web/20080527021506/http://www.wolverinefoundation.org/dentition.htm | archive-date = 27 May 2008 | access-date = 1 July 2007}}</ref><ref name="akfishgame">{{cite web | last = Taylor | first = Ken | title = Wolverine | work = Wildlife Notebook Series | publisher = Alaska Department of Fish & Game | year = 1994 | url = http://www.adfg.state.ak.us/pubs/notebook/furbear/wolverin.php | access-date = 21 January 2007 | url-status = live | archive-url = https://web.archive.org/web/20061206233223/http://www.adfg.state.ak.us/pubs/notebook/furbear/wolverin.php | archive-date = 6 December 2006}}</ref> With variation between species, the most common [[dental formula]] is {{DentalFormula|upper=3.1.3.1|lower=3.1.3.2}}.<ref name=EoM />