Editing Virginia opossum

{{Short description|Species of marsupial}}
{{other uses of|possum|Possum (disambiguation)}}
{{Speciesbox
| name = Virginia opossum<ref name=msw3>{{MSW3 Didelphimorphia | id = 10400045 | page = 6}}</ref>
| fossil_range = {{longitem|style=line-height:1.25em|{{nowrap|[[Irvingtonian|Middle Pleistocene]] – [[Holocene|present]]}} {{nowrap|(~600,000–0 [[Before Present|YBP]])<ref name="Harrington2015"/>}}}}
| image = Opossum 2.jpg
| image_caption = North American opossum in winter
| status = LC
| status_system = IUCN3.1
| status_ref = <ref name="iucn status 19 November 2021">{{cite iucn |author=Pérez-Hernandez, R. |author2=Lew, D. |author3=Solari, S. |date=2016 |title=''Didelphis virginiana'' |volume=2016 |page=e.T40502A22176259 |doi=10.2305/IUCN.UK.2016-1.RLTS.T40502A22176259.en |access-date=19 November 2021}}</ref>
| status2 = G5
| status2_system = TNC
| status2_ref = <ref>{{cite web|title=Didelphis virginiana|url=https://explorer.natureserve.org/Taxon/ELEMENT_GLOBAL.2.106143/Didelphis_virginiana|website=[[NatureServe]] Explorer|access-date=17 April 2024}}</ref>
| genus = Didelphis
| species = virginiana
| authority = ([[Robert Kerr (writer)|Kerr]], 1792)
| synonyms = ''[[Common opossum|Didelphis marsupialis]] virginiana''<ref>{{citation|title=Behavior of Captive Opossums, Didelphis marsupialis virginiana|author=John J. McManus|doi=10.2307/2423733|journal=American Midland Naturalist|volume=84|issue = 1|date=July 1970|pages=144–169|jstor=2423733}}</ref>
| range_map = Virginia Opossum range.png
| range_map_caption = Range of habitat, showing both historic, native range and introductions in the west; these areas are currently expanding northward (e.g., into [[Wisconsin]] and [[Minnesota]]).<ref name="Gardner2003">{{cite book|editor1=Feldhamer, G.A.|editor2= Thompson, B.C.|editor3= Chapman, J.A.|author1= Gardner, A.L.|chapter= Opossum: ''Didelphis virginiana'' |author2= Sunquist, M.E.|title=Wild Mammals of North America: Biology, Management, and Conservation|chapter-url= https://books.google.com/books?id=-xQalfqP7BcC&pg=PA4|year= 2003|publisher=JHU Press|isbn= 978-0-8018-7416-1|pages= 3–29}}</ref>
}}

The '''Virginia opossum''' ('''''Didelphis virginiana'''''), also known as the '''North American opossum''', is a member of the [[opossum]] family found from southern [[Canada]] to northern [[Costa Rica]] (making it the northernmost [[marsupial]] in the world). Commonly referred to simply as the '''possum''',<ref>{{cite web|url=https://www.merriam-webster.com/wordplay/possum-vs-opossum-difference-pronunciation|title=Possum vs. Opossum: Is There a Difference?|publisher=Merriam-Webster|access-date=2023-11-12|quote=Textbooks, encyclopedias, and science publications favor ''opossum'', but when it comes to general speech and writing, ''possum'' is and has been the far more common choice.}}</ref> it is a solitary [[nocturnal animal]] about the size of a [[domestic cat]], and a successful [[Opportunism#Biological|opportunist]].

Opossums are familiar to many North Americans as they frequently inhabit settled areas near food sources like trash cans, pet food, [[compost]] piles, gardens or housemice. Their slow, nocturnal nature and their attraction to roadside [[carrion]] make opossums more likely to become [[roadkill]].

==Name==
The Virginia opossum is the original animal named "[[opossum]]", a word which comes from [[Algonquian languages|Algonquian]] ''wapathemwa'', meaning "white animal". Colloquially, the Virginia opossum is frequently just called a "possum".<ref name="FFM">{{Cite book|title=Florida's Fabulous Mammals|last=Gingerich|first=Jerry Lee|publisher=World Publications|year=1994|isbn=978-0-911977-13-4|location=Tampa, FL|page=2}}</ref> The term is applied more generally to any of the other marsupials of the families [[Didelphidae]] and [[Caenolestidae]]. The generic name (''Didelphis'') is derived from Ancient Greek: {{Transliteration|grc|di}}, "two", and {{Transliteration|grc|delphus}}, "womb".<ref>{{cite book |last=Day |first=Leslie |title=Field Guide to the Natural World of New York City |url=https://books.google.com/books?id=-BoOGYeaQ64C&pg=PT225 |date=10 May 2013 |publisher=JHU Press |isbn=978-1-4214-1149-1 |page=225}}</ref>

The [[Phalangeriformes|possums]] of [[Australia]], whose name derives from their similarity to the American species, are also marsupials, but of the order [[Diprotodontia]].

The Virginia opossum is known in Mexico as ''tlacuache'', ''tacuachi'', and ''tlacuachi'', from the [[Nahuatl language|Nahuatl]] word ''tlacuatzin''.

==Range==
{{more citations needed section|date=September 2018}}
The Virginia opossum's ancestors evolved in [[South America]], but spread into North America as part of the [[Great American Interchange]], which occurred mainly after the formation of the [[Isthmus of Panama]] about 3 million years ago. ''Didelphis'' was apparently one of the later migrants, entering North America about 0.8 million years ago.<ref name = "Woodburne2010">{{cite journal|last1= Woodburne|first1= M.O.|title=The Great American Biotic Interchange: Dispersals, Tectonics, Climate, Sea Level and Holding Pens|journal= Journal of Mammalian Evolution|volume= 17|issue= 4|date= 2010-07-14|pages= 245–264|doi= 10.1007/s10914-010-9144-8|pmid= 21125025|pmc= 2987556}}</ref> It is now found throughout [[Central America]] and [[North America]] from [[Costa Rica]] to southern [[Ontario]] and is expanding its range northward, northwesterly and northeasterly at a significant pace.<ref name="FFM" />

Its pre-European settlement range was generally as far north as [[Maryland]]; southern [[Ohio]], [[Indiana]] and [[Illinois]]; [[Missouri]] and [[Kansas]]. The clearing of dense forests in these areas and further north by settlers allowed the opossum to move northward. Elimination of the opossum's main predators in these areas also contributed to their expansion.   Since 1900, it has expanded its range to include most of [[New England]] (including [[Maine]]); [[New York (state)|New York]], extreme southwestern [[Quebec]]; most of southern and eastern Ontario; most of [[Michigan]] and [[Wisconsin]]; most of [[Minnesota]], southeastern [[South Dakota]] and most of [[Nebraska]].

Areas such as [[Rhode Island]] and [[Waterloo Region]] and [[Simcoe County]] in southern Ontario rarely had sightings of opossums in the 1960s, but now have them regularly; some speculate that this is likely due to global warming causing winters to be warmer.<ref>{{cite journal|last1=Walsh|first1=L. L.|last2=Tucker|first2=P. K.|year=2017|title=Contemporary range expansion of the Virginia opossum (Didelphis virginiana) impacted by humans and snow cover|journal=Canadian Journal of Zoology|volume=96|issue=2|pages=107–115|doi=10.1139/cjz-2017-0071|hdl=1807/81311|hdl-access=free}}</ref> Some people speculate the expansion into Ontario mostly occurred by opossums accidentally being transferred across the [[St. Lawrence River|St. Lawrence]], [[Niagara River|Niagara]], [[Detroit River|Detroit]] and [[St. Clair River|St. Clair]] rivers by motor vehicles or trains they may have climbed upon. As the opossum is not adapted to colder winters or heavy snow, its population may be significantly reduced if a colder winter with heavier snow occurs in a particular northern region.

The Virginia opossum was not originally native to the West Coast of the United States. It was intentionally introduced into the West<ref name="FFM" /> during the [[Great Depression]], probably as a source of food,<ref>''The Opossum: Its Amazing Story'', William J. Krause and Winifred A. Krause, University of Missouri-Columbia, 2006, p. 23, {{ISBN|0-9785999-0-X}}, 9780978599904.</ref> and now occupies much of the Pacific coast. Its range has been expanding steadily northward into [[British Columbia]].

Small isolated populations of Opossums also occur in Eastern [[New Mexico]] and parts of Southern and Central [[Arizona]], particularly around [[Tucson, Arizona|Tucson]]. It is unknown if these populations are native to these regions or were introduced at some point.<ref>{{Cite web |title=Opossums in Arizona? – Arizona Daily Independent |url=https://arizonadailyindependent.com/2017/01/22/opossums-in-arizona/ |access-date=2025-02-08 |website=arizonadailyindependent.com}}</ref>

==Description==
[[File:Opossum Skull.jpg|thumb|Skull of a Virginia opossum|alt=]]
[[File:Virginia opossum opposable thumb.jpg|alt=|thumb|The back foot has an opposable "thumb".]]
Virginia opossums can vary considerably in size, with larger specimens found to the north of the opossum's range and smaller specimens in the tropics. They measure {{cvt|33–55|cm}} long from their snout to the base of the tail, with the tail adding another {{cvt|25|–|54|cm}}. Males are slightly larger, with an average body length of {{cvt|40.8|cm}} with an average tail length of {{cvt|29.4|cm}}, while females are {{cvt|40.6|cm}} long with a {{cvt|28.1|cm}} tail. Weight for males ranges from {{cvt|2.1–2.8|kg}} and for females from {{cvt|1.9|–|2.1|kg}}.<ref>{{Cite web|url=http://animaldiversity.ummz.umich.edu/site/accounts/information/Didelphis_virginiana.html|title=ADW: Didelphis virginiana: Information (1974-05-02)|website=animaldiversity.ummz.umich.edu|access-date=2011-09-15}}</ref>

Their coats are a dull grayish brown, other than on their faces, which are white. Opossums have long, hairless, [[prehensile]] tails, which can be used to grab branches and carry small objects. They also have hairless ears and a long, flat nose. Opossums have [[dentition|50 teeth]], more than any other North American land mammal,<ref>[http://web.extension.illinois.edu/wildlife/directory_show.cfm?species=opossum Wildlife Directory: Virginia Opossum — Living with Wildlife — University of Illinois Extension] {{Webarchive|url=https://web.archive.org/web/20180513144116/http://web.extension.illinois.edu/wildlife/directory_show.cfm?species=opossum |date=2018-05-13 }}. Web.extension.illinois.edu. Retrieved on 2011-09-15.</ref> and opposable, clawless thumbs on their rear limbs. Opossums have 13 [[nipple]]s, arranged in a circle of 12 with one in the middle.<ref>[http://digitalcollections.fiu.edu/wild/transcripts/possums1.htm With the Wild Things - Transcripts] {{Webarchive|url=https://web.archive.org/web/20130323001102/http://digitalcollections.fiu.edu/wild/transcripts/possums1.htm |date=2013-03-23 }}. Digitalcollections.fiu.edu. Retrieved on 2011-09-15.</ref><ref>Mary Stockard, AWRC Mammal Supervisor (2001) [https://web.archive.org/web/20041223190821/http://www.awrc.org/Baby%20Opossums.htm Raising Orphaned Baby Opossums]. AWRC.org</ref>

The dental formula of an opossum is {{DentalFormula|upper=5.1.3.4|lower=4.1.3.4}}.<ref>{{Cite web|url=http://www.nsrl.ttu.edu/tmot1/didevirg.htm|title=Virginia Opossum (Didelphis virginiana)|website=www.nsrl.ttu.edu|access-date=2018-11-11}}</ref> No other mammal in North America has more than 6 upper [[incisor]]s, but the Virginia opossum has 10.

Perhaps surprisingly for such a widespread and successful species, the Virginia opossum has one of the lowest [[encephalization quotient]]s of any marsupial.<ref>{{cite journal
  | last = Ashwell
  | first = K.w.s. 
  | title = Encephalization of Australian and New Guinean Marsupials
  | journal = Brain, Behavior and Evolution
  | volume = 71
  | issue = 3
  | pages = 181–199
  | date = April 2008
  | issn = 0006-8977
  | doi = 10.1159/000114406
  | pmid = 18230970| s2cid = 7544968 
 }}
</ref>
Its brain is one-fifth the size of a raccoon's.<ref name=Audubon>{{cite web|url=http://www.massaudubon.org/Nature_Connection/wildlife/index.php?subject=Mammals&id=71|title=Virginia Opossum|publisher=Mass Audubon|access-date=May 11, 2011|quote=Opossums are frequently encountered as corpses along highways. Some biologists believe that many die as they feed on road-killed animals – a favorite food. Others believe that the opossums’ small brain (5 times smaller than that of a [[raccoon]][sic - erroneous logic]) suggests that they may just be too dumb to get out of the way of vehicles!|archive-date=December 29, 2010|archive-url=https://web.archive.org/web/20101229120106/http://www.massaudubon.org/Nature_Connection/wildlife/index.php?subject=Mammals&id=71|url-status=dead}}</ref>

===Tracks===
{{more citations needed section|date=March 2018}}
{{Multiple image
| image1            = Opossum and vole tracks in mud.JPG
| caption1          = Opossum tracks (photo center) in mud: Left-fore print appears on left center of photo, right-hind print appears right center. The small, circular tracks at bottom center of photo were made by a meadow vole. The yellow ruler (top) is in inches.
| image2            = Pacing diagram opossum.png
| caption2          = Pacing diagram for Virginia opossum - key: rectangles represent hind tracks, ellipses are fore tracks, left tracks are red, right are green. (a) the position of the four feet frozen in mid-pace. (b) the opossum brings right fore and hind feet forward. (c) the opossum brings left fore and hind feet forward. One grid square represents one square inch.
| total_width       = 350
}}
Virginia opossum tracks generally show five finger-like toes in both the fore and hind prints.<ref name=Krause>Krause, William J.; Krause, Winifred A. (2006).[https://web.missouri.edu/~krausew/Histology/Home_files/opossum.pdf  ''The Opossum: Its Amazing Story''] {{Webarchive|url=https://web.archive.org/web/20121211214644/https://web.missouri.edu/~krausew/Histology/Home_files/opossum.pdf |date=2012-12-11 }}. Department of Pathology and Anatomical Sciences, School of Medicine, University of Missouri, Columbia, Missouri. 80 pages.</ref> The hind tracks are unusual and distinctive due to the opossum's opposable [[thumb]], which generally prints at an angle of 90° or greater to the other fingers (sometimes near 180°). Individual adult tracks generally measure 1.9 in long by 2.0&nbsp;in wide (4.8 × 5.1&nbsp;cm) for the fore prints and 2.5 in long by 2.3 in wide (6.4 × 5.7&nbsp;cm) for the hind prints. Opossums have claws on all fingers fore and hind except on the two thumbs (in the photograph, claw marks show as small holes just beyond the tip of each finger); these generally show in the tracks. In a soft medium, such as the mud in this photograph, the foot pads clearly show (these are the deep, darker areas where the fingers and toes meet the rest of the hand or foot, which have been filled with plant debris by wind due to the advanced age of the tracks).

The tracks in the photograph were made while the opossum was walking with its typical pacing [[gait]]. The four aligned toes on the hind print show the approximate direction of travel.

In a pacing gait, the limbs on one side of the body are moved simultaneously, just prior to moving both limbs on the other side of the body. This is illustrated in the pacing diagram, which explains why the left-fore and right-hind tracks are generally found together (and vice versa). If the opossum was not walking (perhaps running), the prints would fall in a different pattern. Other animals that generally employ a pacing gait are [[raccoon]]s, [[bear]]s, [[skunk]]s, [[badger]]s, [[woodchuck]]s, [[porcupine]]s, and [[beaver]]s.

When pacing, the opossum's 'stride' generally measures from 7 to 10&nbsp;in, or 18 to 25&nbsp;cm (in the pacing diagram the stride is 8.5&nbsp;in, where one grid square is equal to 1 in<sup>2</sup>). To determine the stride of a pacing gait, measure from the tip (just beyond the fingers or toes in the direction of travel, disregarding claw marks) of one set of fore/hind tracks to the tip of the next set. By taking careful stride and track-size measurements, one can usually determine what species of animal created a set of tracks, even when individual track details are vague or obscured.

== Behavior ==
=== "Playing possum" ===
[[File:PlayingPossum.jpg|thumb|When injured or threatened (e.g., by a dog), the Virginia opossum is known to [[feign death]] or "play possum".|alt=]]If threatened, an opossum will either flee or take a stand. To appear threatening, an opossum will first bare its 50 teeth, snap its jaw, hiss, drool, and stand its fur on end to look bigger.<ref name=":72">{{Cite web|title=Virginia Opossum|url=https://www.psu.edu/dept/nkbiology/naturetrailOLD/speciespages/opossum.htm|access-date=2020-09-28|website=www.psu.edu |archive-url=https://web.archive.org/web/20100601193804/https://www.psu.edu/dept/nkbiology/naturetrailOLD/speciespages/opossum.htm |archive-date=2010-06-01 |url-status=dead}}</ref> If this does not work, the Virginia opossum is noted for [[Apparent death|feigning death]] in response to extreme fear.<ref name=":82">{{Cite web|title=Opossum Defense Mechanisms {{!}} Opossum Society of the United States|url=https://opossumsocietyus.org/general-opossum-information/opossum-defense-mechanisms/|access-date=2020-09-28|language=en-US}}</ref> This is the genesis of the term "playing possum", which means pretending to be dead or injured with intent to deceive.<ref>{{Cite web|title=PLAY POSSUM {{!}} definition in the Cambridge English Dictionary|url=https://dictionary.cambridge.org/us/dictionary/english/play-possum|access-date=2020-09-28|website=dictionary.cambridge.org|language=en-US}}</ref>

In this inactive state it lies limp and motionless on its side, mouth and eyes open, tongue hanging out, and feet clenched.<ref name=":72" /> Fear can also cause the opossum to release a green fluid from its anus with a putrid odor that repels predators.<ref name=":82" /><ref name=":142">{{Cite web|title=Give opossums a break|url=https://www.caryinstitute.org/news-insights/media-coverage/give-opossums-break|access-date=2020-09-30|website=Cary Institute of Ecosystem Studies|date=30 March 2015 |language=en}}</ref> Heart rate drops by half, and breathing rate is so slow and shallow it is hardly detectable.<ref name=":72" /> Death feigning normally stops when the threat withdraws, and it can last for several hours.<ref name=":72" /><ref name=":142" /> Besides discouraging animals that eat live prey, playing possum also convinces some large animals that the opossum is no threat to their young.<ref name=":82" /> "Playing possum" in response to threats from oncoming traffic often results in death.<ref name=":92">{{Cite web|title=Why you should brake for opossums|url=https://www.caryinstitute.org/news-insights/podcast/why-you-should-brake-opossums|access-date=2020-09-28|website=Cary Institute of Ecosystem Studies|date=23 July 2012 |language=en}}</ref>

=== Diet ===
[[File:Possum rejects bagel.webm|thumb|Night camera shows video of an opossum considering a bagel before walking away]]
Opossums are [[Omnivore|omnivorous]] (sometimes said to be [[insectivorous]]) and eat a wide range of plant-based food, as well as animal-based food like small invertebrates, [[carrion]], eggs, fish, amphibians, reptiles, birds, small mammals, and other small animals.<ref name=":102">{{Cite web|date=2018-01-05|title=Virginia opossum|url=https://nationalzoo.si.edu/animals/virginia-opossum|access-date=2020-09-28|website=Smithsonian's National Zoo|language=en}}</ref>

[[Insects]] such as grasshoppers, crickets, and beetles make up the bulk of the animal foods eaten by opossums.<ref name=":112">{{Cite web|title=Opossum {{!}} Adirondack Ecological Center {{!}} SUNY ESF {{!}} College of Environmental Science and Forestry|url=https://www.esf.edu/aec/adks/mammals/opossum.htm#:~:text=Social%20system%20-%20Opossums%20are%20solitary,may%20share%20a%20winter%20den.|access-date=2020-09-28|website=www.esf.edu}}</ref> It has been stated that opossums eat up to 95% of the [[tick]]s they encounter<ref name=":92"/><ref name=":13">{{Cite web|last=Maurer|first=Steph|title=The Helpful Opossum {{!}} Wildlife Medical Clinic at Illinois|url=https://vetmed.illinois.edu/wildlife/2019/06/05/the-helpful-opossum-2/|access-date=2022-04-24|language=en-US |archive-url=https://web.archive.org/web/20210716193836/https://vetmed.illinois.edu/wildlife/2019/06/05/the-helpful-opossum-2/ |archive-date=2021-07-16 |url-status=dead}}</ref> and may eat up to 5,000 ticks per season, helping to prevent the spread of tick-born illnesses, including [[Lyme disease]] and [[Rocky Mountain spotted fever]].<ref name=":13" /> This interpretation has been challenged.<ref name="Hennessy2021">{{cite journal |last1=Hennessy |first1=C. |last2=Hild |first2=K. |date=September 2021 |title=Are Virginia opossums really ecological traps for ticks? Groundtruthing laboratory observations |url=https://www.sciencedirect.com/science/article/abs/pii/S1877959X21001333 |journal=Ticks and Tick-Borne Diseases |volume=12 |issue=5 |page=101780 |doi=10.1016/j.ttbdis.2021.101780 |pmid=34298355 |access-date=2022-04-20}}</ref>  A widely publicized 2009 study by the [[Cary Institute of Ecosystem Studies|Cary Institute]] indicated that Virginia opossums in a laboratory setting could eat thousands of ticks per week [[Personal grooming#In animals|grooming]].<ref>{{cite web |last1=Kirchner |first1=Jane |title=Opossums: Unsung Heroes in the Fight Against Ticks and Lyme Disease |url=https://blog.nwf.org/2017/06/opossums-unsung-heroes-in-the-fight-against-ticks-and-lyme-disease/ |website=National Wildlife Federation |date=13 June 2017 |access-date=26 August 2019}}</ref><ref>{{cite news |last1=Bayly |first1=Julia |title=Turns out, opossums may not actually like eating ticks |url=https://www.bangordailynews.com/2022/03/24/homestead/turns-out-opossums-dont-really-like-eating-ticks-xoasq1i29i/ |access-date=27 October 2022 |work=Bangor Daily News |date=24 March 2022}}</ref> However, subsequent studies of the stomach contents of wild Virginia opossums have not found any ticks in their diet.<ref>{{cite journal |last1=Hennessy |first1=Cecilia |last2=Hild | first2=Kaitlyn |title=Are Virginia opossums really ecological traps for ticks? Groundtruthing laboratory observations |url=https://pubmed.ncbi.nlm.nih.gov/34298355/ |journal=Ticks and Tick-Borne Diseases |date=15 July 2021 |volume=12 |issue=5 |page=101780 |doi=10.1016/j.ttbdis.2021.101780 |pmid=34298355 |access-date=18 January 2021}}</ref>

Small animals include young rabbits, meadow voles, mice, rats, birds, snakes, lizards, frogs, fish, crayfish, gastropods, and earthworms.<ref name=":12">{{Cite web|title=Opossum Management Guidelines--UC IPM|url=http://ipm.ucanr.edu/PMG/PESTNOTES/pn74123.html#:~:text=Opossums%20carry%20diseases%20such%20as,fleas,%20especially%20in%20urban%20environments.|access-date=2020-09-28|website=ipm.ucanr.edu}}</ref><ref>{{Cite web|url=https://www.chesapeakebay.net/S=0/fieldguide/critter/virginia_opossum|title=Virginia Opossum &#124; Chesapeake Bay Program|website=www.chesapeakebay.net}}</ref><ref>{{Cite web|url=https://lafeber.com/vet/basic-information-sheet-virginia-opossum/|title=Basic Information Sheet: Virginia Opossum|date=June 11, 2018}}</ref><ref>{{Cite web|url=https://aaric.org/2020/09/11/virginia-opossum/|title=Virginia opossum|date=September 11, 2020}}</ref><ref name="Martina">{{Cite web|url=https://animaldiversity.org/accounts/Didelphis_virginiana/|title=Didelphis virginiana (Virginia opossum)|first=Leila Siciliano|last=Martina|website=Animal Diversity Web}}</ref> The Virginia opossum has been found to be very resistant to snake venom.<ref>{{cite journal|author=Sharon A. Jansa|author2=Robert S. Voss|year=2011|title=Adaptive evolution of the venom-targeted vWF protein in opossums that eat pitvipers|journal=PLOS ONE|volume=6|issue=6|pages=e20997|doi=10.1371/journal.pone.0020997|pmc=3120824|pmid=21731638|bibcode=2011PLoSO...620997J|doi-access=free}}</ref><ref name=":13" /> Attracted to carrion on the side of the highway, opossums are at an increased risk of being hit by motor vehicles.<ref name=":142"/>

Plant foods are mainly eaten in late summer, autumn, and early winter.<ref name=":112"/> These include raspberries, blackberries, apples, acorns, beechnuts, seeds, grains, bulbs, and vegetables.<ref name=":112"/><ref name="Martina"/> [[Diospyros virginiana|Persimmons]] are one of the opossum's favorite foods during the autumn.<ref>Sparano, Vin T. 2000. The Complete outdoors encyclopedia. St. Martin's Press. {{ISBN|0-312-26722-3}}</ref> Opossums in urban areas scavenge from bird feeders, vegetable gardens, compost piles, garbage cans, and food dishes intended for dogs and cats.<ref name=":112"/><ref name=":12" />[[File:Possum122708.JPG|thumb|Virginia opossum in northeastern Ohio]]

Opossums in captivity are known to engage in [[cannibalism]], though this is probably uncommon in the wild.<ref>[http://www.opossumsocietyus.org/cannibalism_in_the_opossum.htm Cannibalism in the Opossum]. Opossum Society. Accessed May 7, 2007.</ref> Because of this, placing an injured opossum in a confined space with its healthy counterparts is inadvisable.

=== Seasonality ===
The Virginia opossum is most active during the spring and summer.<ref name=":112" /> It does not hibernate but reduces its activity during the winter.<ref name=":102" /><ref>{{cite web|title=Virginia Opossum Didelphis virginiana|url=http://enature.com/fieldguides/detail.asp?allSpecies=y&searchText=opossum&curGroupID=5&lgfromWhere=&curPageNum=1|url-status=dead|archive-url=https://web.archive.org/web/20110517185002/http://enature.com/fieldguides/detail.asp?allSpecies=y&searchText=opossum&curGroupID=5&lgfromWhere=&curPageNum=1|archive-date=2011-05-17|access-date=2009-03-24|work=eNature.com|publisher=Shearwater Marketing Group}}</ref> It may not leave its den for several days if the temperature drops below {{convert|-7|to|-4|C|F}}.<ref name=":112" /> Both males and females are at greater risk of injury during breeding season.<ref name=":15">{{Cite web|title=Reproduction – Life Cycle {{!}} Opossum Society of the United States|url=https://opossumsocietyus.org/general-opossum-information/opossum-reproduction-lifecycle/|access-date=2020-09-30|language=en-US}}</ref> Males extend their range in search of mates which puts them at greater risk of injury from motor vehicles and predators as they venture into unfamiliar territory.<ref name=":15" /> Females carrying young are slower moving and have to forage earlier in the evening and later into the night, also increasing their risk of injury from motor vehicles and predation.<ref name=":15" />

===Reproduction===
[[File:Didelphis virginiana with young.JPG|thumb|Carrying her young]]The breeding season for the Virginia opossum can begin as early as December and continue through October with most young born between February and June.<ref name=":15" /> A female opossum may have one to three litters per year.<ref name=":15" /> During the mating season, the male attracts the female by making clicking sounds with his mouth.<ref name=":15" /> The female's [[Estrous cycle|estrus cycle]] is 28 days and lasts 36 hours.<ref name=":15" /> Gestation lasts 11–13 days and the average litter size is 8–9 infants, although over 20 infants may be born.<ref name=":15" />  Opossums have a very high [[mortality rate]] of their young; only one in ten offspring survive to reproductive adulthood.<ref>{{cite book|last1=Tyndale-Biscoe|first1=Hugh|title=Life of marsupials|date=2008|publisher=CSIRO|isbn=9780643092204|edition=[New.]|location=Collingwood|pages=105–138}}</ref>

Newborns are the size of a [[Honey bee|honeybee]].<ref name=":112" /> Once delivered through the median vagina or central birth canal, newborn opossums climb up into the female opossum's pouch and latch onto one of her 13 teats.<ref name=":15" /> The young remain latched for two months and in the pouch for {{frac|2|1|2}} months.<ref name=":15" /> The young then climb onto the mother's back, where she carries them for the remainder of their time together.<ref name=":15" /> It is during this time that the young learn survival skills.<ref name=":15" /> They leave their mother after about four or five months.<ref>{{cite web|title=Reproduction – Life Cycle - Opossum Society of the United States|url=http://opossumsocietyus.org/general-opossum-information/opossum-reproduction-lifecycle/|website=opossumsocietyus.org}}</ref>

Like all female [[marsupial]]s, the female's reproductive system is bifid, with two lateral vaginae, uteri, and ovaries.<ref name=":16">{{Cite book|last=Krause|first=William J.|title=The Opossum: Its Amazing Story|publisher=Department of Pathology and Anatomical Sciences, School of Medicine, University of Missouri, Columbia, Missouri|year=2005|isbn=0-9785999-0-X}}</ref> The male's penis is also bifid, with two heads, and as is common in New World marsupials, the sperm pair up in the testes and only separate as they come close to the egg.<ref name=":16" />  Males have three pairs of [[Cowper's gland]]s.<ref>Martan, Jan. [https://ilacadofsci.com/wp-content/uploads/2013/09/076-01-print.pdf "The genital tract of the male opossum Didelphis marsupialis virginiana and other marsupials."] Trans. I 11 (1983): 3-28.</ref>

==Lifespan==
Compared to other mammals, including most other marsupials except [[dasyuromorphia]]ns, opossums have unusually short lifespans for their size and metabolic rate.<ref name="Krause2">Krause, William J.; Krause, Winifred A. (2006).[https://web.missouri.edu/~krausew/Histology/Home_files/opossum.pdf ''The Opossum: Its Amazing Story''] {{Webarchive|url=https://web.archive.org/web/20121211214644/https://web.missouri.edu/~krausew/Histology/Home_files/opossum.pdf|date=2012-12-11}}. Department of Pathology and Anatomical Sciences, School of Medicine, University of Missouri, Columbia, Missouri. 80 pages.</ref><ref>{{cite journal|last1=Fisher|first1=Diana O.|last2=Owens|first2=Ian P. F.|last3=Johnson|first3=Christopher N.|date=2001|title=The ecological basis of life history variation in marsupials|url=https://espace.library.uq.edu.au/view/UQ:60315/UQ60315_OA.pdf |archive-url=https://web.archive.org/web/20170824141620/http://espace.library.uq.edu.au/view/UQ:60315/UQ60315_OA.pdf |archive-date=2017-08-24 |url-status=live|journal=Ecology|volume=82|issue=12|pages=3531–3540|doi=10.1890/0012-9658(2001)082[3531:TEBOLH]2.0.CO;2}}</ref> The Virginia opossum has a maximal lifespan in the wild of only about two years.<ref>[http://www.gpnc.org/opossum.htm Virginia Opossum. Didelphis virginiana] {{Webarchive|url=https://web.archive.org/web/20071024000827/http://www.gpnc.org/opossum.htm|date=2007-10-24}}. Great Plains Nature Center. accessed Oct. 15, 2007</ref> Even in captivity, opossums live only about four years.<ref>[http://sonic.net/~petdoc/lifespan.htm The Life Span of Animals] Accessed Oct. 15, 2007</ref> The rapid [[senescence]] of opossums is thought to reflect the fact that they have few defenses against predators; given that they would have little prospect of living very long regardless, they are not under [[selective pressure]] to develop biochemical mechanisms to enable a long lifespan.<ref name="Wright2">Karen Wright [https://www.discovermagazine.com/health/staying-alive-02 Staying Alive]. Discover Magazine. November 6, 2003 Accessed Oct 15, 2007.</ref> In support of this hypothesis, one population on [[Sapelo Island]], {{convert|5|mi|0}} off the coast of [[Georgia (U.S. state)|Georgia]], which has been isolated for thousands of years without natural predators, was found by Dr. Steven Austad to have evolved lifespans up to 50% longer than those of mainland populations.<ref name="Wright2" /><ref>{{cite web|title=State Of Tomorrow™ - Rising Challenges. Higher Education Solutions.|url=http://www.stateoftomorrow.com/stories/aging/austad.htm|website=www.stateoftomorrow.com}}</ref>

==Historical references==
An early description of the opossum comes from explorer [[John Smith of Jamestown|John Smith]], who wrote in ''Map of Virginia, with a Description of the Countrey, the Commodities, People, Government and Religion'' in 1608 that "An Opassom hath an head like a Swine, and a taile like a Rat, and is of the bignes of a Cat. Under her belly she hath a bagge, wherein she lodgeth, carrieth, and sucketh her young."<ref>[https://web.archive.org/web/20080603030757/http://wordsmithradio.org/scripts/opossum.html Chrysti the Wordsmith > Radio Scripts > Opossum]. Retrieved 2009-12-29.</ref><ref>[http://www.possumnetwork.com/history.htm Possum History] {{Webarchive|url=https://web.archive.org/web/20110715105935/http://www.possumnetwork.com/history.htm |date=2011-07-15 }}. Retrieved 2009-12-29.</ref>
The opossum was more formally described in 1698 in a published letter entitled "''Carigueya, Seu Marsupiale Americanum Masculum''. Or, The Anatomy of a Male Opossum: In a Letter to Dr Edward Tyson", from Mr [[William Cowper (anatomist)|William Cowper]], Chirurgeon, and [[Fellow of the Royal Society]], London, by Edward Tyson, M.D. Fellow of the College of Physicians and of the Royal Society. The letter suggests even earlier descriptions.<ref>{{cite journal |title=The Panniculus Carnosus and Pouch Musculature of the Opossum, a Marsupial |first=Orthello R. |last=Langworthy |journal=Journal of Mammalogy |volume= 13 |issue= 3 |year=1932 |pages=241–251 |doi=10.2307/1373999 |jstor=1373999}}</ref>

==Relationship with humans==
[[File:American opossum in baby grand piano.jpg|thumbnail|right|Virginia opossum cornered in a piano in Houston, Texas, shortly before its release]]

Opossums are not considered dangerous to humans.<ref>{{Cite web |title=Are opossums dangerous? They can be, but they're also good for your backyard. |url=https://www.usatoday.com/story/news/2022/11/07/are-possums-opossums-dangerous-animals/7941384001/ |access-date=2023-12-25 |website=USA TODAY |language=en-US}}</ref> Though their open-mouth hiss when frightened is often mistaken as rabid behavior, opossums are naturally resistant to [[rabies]] due to their low body temperature. Opossums can however host parasites and carry diseases such as [[tuberculosis]], [[leptospirosis]], and [[tularemia]], among others.<ref>{{Cite web |last=Weinberger |first=Dawn |date=2023-10-19 |title=Are Opossums Dangerous To Humans, Pets And Property? |url=https://www.forbes.com/home-improvement/pest-control/are-opossums-dangerous/ |access-date=2023-12-25 |website=Forbes Home |language=en-US}}</ref> 

Like raccoons, opossums can be found in urban environments, where they eat pet food, rotten fruit, and human garbage. They also are considered a common predator of [[poultry farming]] in North America.<ref name="Ohioline-2018">{{cite web |date=2018-12-20 |title=Predators of Poultry |url=http://ohioline.osu.edu/factsheet/vme-22 |access-date=2022-04-21 |website=Ohioline [[Ohio State University]]}}</ref><ref name="Extension-predators">{{cite web |title=Predator Management for Small and Backyard Poultry Flocks |url=http://poultry.extension.org/articles/poultry-management/predator-management-for-small-and-backyard-poultry-flocks/ |access-date=2022-04-21 |website=[[Cooperative Extension]] Poultry}}</ref> Research suggests that proximity to humans causes an increase in body size for opossums living in or near urban environments.<ref>{{Cite journal|last=Wright|date=2012|title=Influences of an Urban Environment on Home Range and Body Mass of Virginia Opossums (Didelphis virginiana)|journal=Northeastern Naturalist|volume=19|issue=1|pages=77–86|jstor=41429417|doi=10.1656/045.019.0106|s2cid=86663111}}</ref> Though sometimes mistakenly considered to be rats, opossums are not closely related to [[rodent]]s or any other [[placental]] mammals.

The opossum was once a favorite game animal in the [[United States]], particularly in the southern regions which have a large body of recipes and folklore relating to it.<ref>[https://www.espn.com/outdoors/general/columns/story?columnist=sutton_keith&id=3827266  Keith Sutton. Possum days gone by. ESPN Outdoors. January 12, 2009]. Retrieved 2009-12-29.</ref> Their past wide consumption in regions where present is evidenced by recipes available online<ref>[http://www.wildgamerecipes.org/ Wild Game Recipes online]. Retrieved 2009-12-29.</ref> and in books such as older editions of ''[[The Joy of Cooking]]''.<ref>[http://www.ethicurean.com/2006/10/14/joy-of-cooking/ The joy of the ‘Joy of Cooking,’ circa 1962] {{Webarchive|url=https://web.archive.org/web/20061030204530/http://www.ethicurean.com/2006/10/14/joy-of-cooking/ |date=2006-10-30 }}. Retrieved 2009-12-29.</ref> A traditional method of preparation is baking, sometimes in a pie or pastry,<ref>[http://writers-bbs.com/html/FishEggs/3.98/5.html opossum pie] {{Webarchive|url=https://web.archive.org/web/20110718121624/http://writers-bbs.com/html/FishEggs/3.98/5.html |date=2011-07-18 }}. Retrieved 2009-12-29.</ref> though at present "possum pie" most often refers to a sweet confection containing no meat of any kind.<ref>{{cite web |last1=Burke |first1=Peter |title=Arkansas dessert with an animal in its name is award-winning treat with 'no possum included' |url=https://www.foxnews.com/food-drink/arkansas-dessert-animal-name-award-winning-treat-no-possum-included |website=Fox News |access-date=17 December 2024 |date=5 December 2024}}</ref>

Around the turn of the 20th century, the opossum was the subject of numerous songs, including "Carve dat Possum", a minstrel song written in 1875 by Sam Lucas.<ref>{{Cite web|title=Carve dat possum|url=https://www.loc.gov/item/sm1875.10894/|access-date=2020-11-09|website=Library of Congress}}</ref>

Although it is widely distributed in the United States, the Virginia opossum's appearance in folklore and popularity as a food item has tied it closely to the American [[Southeastern United States|Southeast]]. In animation, it is often used to depict uncivilized characters or "[[hillbilly|hillbillies]]". Not surprisingly, then, the Virginia opossum is featured in several episodes of the hit TV show ''[[The Beverly Hillbillies]]'', such as the "Possum Day" episode in 1965.<ref>{{Cite web|url=https://www.imdb.com/title/tt0522552/|title=Possum Day|date=October 13, 1965|via=IMDb}}</ref> The title character in [[Walt Kelly]]'s long-running comic strip ''[[Pogo (comics)|Pogo]]'' was an opossum. In an attempt to create another icon like the [[teddy bear]], [[president of the United States|President]] [[William Howard Taft]] was tied to the character Billy Possum.<ref>[http://www.possumnetwork.com/politics.htm Possum Politics] {{Webarchive|url=https://web.archive.org/web/20061216150251/http://www.possumnetwork.com/politics.htm |date=2006-12-16 }}. 'Possum Network.  Last accessed November 19, 2006.</ref><ref>[http://www.cyberbee.com/campaign/postcard.html Political Postcards]. Cyberbee learning.  Last accessed November 19, 2006.</ref> The character did not do well, as public perception of the opossum led to its downfall. In December 2010, a cross-eyed Virginia opossum in Germany's [[Leipzig Zoo]] named [[Heidi (opossum)|Heidi]] became an international celebrity.<ref name="reuters">Kelsey, Eric. (January 11, 2011). "[https://news.yahoo.com/s/nm/20110111/od_nm/us_germany_opossum_odd Cross-eyed opossum capturing hearts]". Reuters. Retrieved January 12, 2011.</ref> She appeared on a TV talk show to predict the 2011 Oscar winners, similar to the World Cup predictions made previously by [[Paul the Octopus]], also in Germany.<ref>Kelsey, Eric. (28 February 2011). "[https://web.archive.org/web/20120830013146/http://af.reuters.com/article/oddlyEnoughNews/idAFTRE71R32A20110228 German celebrity opossum misses one Oscar pick]". [[Reuters]]. Retrieved 6 March 2011.</ref>

The [[Perelman Building]] in [[Philadelphia, Pennsylvania]], an annex of the [[Philadelphia Museum of Art]], was formerly the Fidelity Mutual Life Insurance Company Building. Built in the late 1920s its facade is decorated with polychrome sculptures of animals symbolizing various attributes of insurance, including a possum to represent "protection".<ref>{{cite web |last1=Keyes |first1=Norman |title=About the Ruth and Raymond G Perelman Building |url=https://legacyweb.philamuseum.org/doc_downloads/pressroom/perelmanBuilding/pressKits/perelmanBuilding.pdf |website=Philadelphia Museum of Art |access-date=4 May 2025 |archive-url=https://web.archive.org/web/20221020114409/https://legacyweb.philamuseum.org/doc_downloads/pressroom/perelmanBuilding/pressKits/perelmanBuilding.pdf |archive-date=20 October 2022 |pages=2 |url-status=live}}</ref>

==References==
{{Reflist|refs=

<ref name="Harrington2015">{{Cite web|title=''Didelphis virginiana'' - Florida Vertebrate Fossils|last=Harrington|first=Arianna|orig-date=28 April 2015|date=12 May 2015|editor1=Hulbert Jr., Richard C.|editor2=Valdes, Natali|website=Florida Museum|publisher=University of Florida|url=https://www.floridamuseum.ufl.edu/florida-vertebrate-fossils/species/didelphis-virginiana/|access-date=17 April 2024}}</ref>

}}

==External links==
{{Commons|Didelphis virginiana}}
{{Wikispecies|Didelphis virginiana}}
*[http://www.opossum.org/ The National Opossum Society]
*[http://www.opossumsocietyus.org/ Opossum Society of the United States]
*{{Cite Collier's|wstitle=Virginian Opossum |short=x}}

{{Didelphimorphia|D.}}
{{North American Game}}
{{Taxonbar|from=Q147267}}
{{Authority control}}

[[Category:Opossums|Virginia]]
[[Category:Extant Middle Pleistocene first appearances]]
[[Category:Pleistocene mammals of North America]]
[[Category:Marsupials of Central America]]
[[Category:Marsupials of North America]]
[[Category:Mammals of Canada]]
[[Category:Mammals of the United States]]
[[Category:Mammals of Mexico]]
[[Category:Fauna of the Plains-Midwest (United States)]]
[[Category:Fauna of the Southeastern United States|Virginia opossum]]
[[Category:Fauna of the California chaparral and woodlands]]
[[Category:Fauna of the Great Plains]]
[[Category:Ecology of the Appalachian Mountains|Virginia opossum]]
[[Category:Natural history of Virginia|Virginia opossum]]<!--namesake-->
[[Category:Mammals described in 1792]]
[[Category:Articles containing video clips]]
[[Category:Fauna of the Northeastern United States]]
[[Category:Symbols of North Carolina]]
[[Category:Taxa named by Robert Kerr (writer)]]