Editing Old World monkey (section)

{{Short description|Family of mammals}}
{{Automatic taxobox
| name = Old World monkeys<ref name=msw3>{{MSW3 Groves|pages=152–178}}</ref>
| fossil_range = {{Fossil range|Oligocene|Recent}}
| image = Olive baboon Ngorongoro.jpg
| image_caption = [[Olive baboon]] (''Papio anubis'')
| taxon = Cercopithecidae
| display_parents = 2
| authority = [[John Edward Gray|Gray]], 1821<ref name=JEG>{{Cite journal|last=Gray|first=J.E.|date=1821|title=On the natural arrangement of vertebrose animals|url=https://archive.org/stream/londonmedicalre08unkngoog#page/n309/mode/2up|journal=London Medical Repository|volume=15|issue=1|pages=296–310}}</ref>
| parent_authority = [[John Edward Gray|Gray]], 1821<ref name=JEG/>
| type_genus = ''[[Cercopithecus]]''
| type_genus_authority = Linnaeus, 1758
| range_map = OldWorldMonkeys_SpeciesDensity.png
| range_map_caption = The distribution and density of Old World monkey species
| subdivision_ranks = Subfamilies
| subdivision = *[[Cercopithecinae]] – 13 genera<br />
*[[Colobinae]] – 10 genera
}}

'''Old World monkeys''' are [[primate]]s in the [[family (biology)|family]] '''Cercopithecidae''' ({{IPAc-en|ˌ|s|ɜr|k|oʊ|p|ᵻ|ˈ|θ|ɛ|s|ᵻ|d|iː}}). Twenty-four [[genus|genera]] and 138 [[species]] are recognized, making it the largest primate family. Old World monkey genera include [[baboon]]s (genus ''[[Papio]]''), red colobus (genus ''[[Red colobus|Piliocolobus]]''), and [[macaque]]s (genus ''[[Macaca (genus)|Macaca]]''). Common names for other Old World monkeys include the [[talapoin]], [[guenon]], [[colobus]], [[douc]] (douc langur, genus ''[[Pygathrix]]''), [[vervet]], [[gelada]], [[mangabey]] (a group of genera), [[langur]], [[mandrill]], [[drill (animal)|drill]], [[surili]] (''[[Presbytis]]''), [[patas]], and [[proboscis monkey]].

Phylogenetically, they are more closely related to [[ape]]s than to [[New World monkey]]s, with the Old World monkeys and apes diverging from a common ancestor between 25 million and 30 million years ago.<ref>{{Cite web |title=Fossils Indicate Common Ancestor for Old World Monkeys and Apes |last1=Palmer |first1=Chris |last2=magazine |first2=Nature |work=Scientific American |date= |access-date=11 December 2023 |url= https://www.scientificamerican.com/article/fossils-indicate-common-ancestor-old-world-monkeys-apes/ |quote=25 million to 30 }}</ref> This [[Cladistics|clade]], containing  the Old World monkeys and the apes, diverged from a common ancestor with the New World monkeys around 45 to 55&nbsp;million years ago.<ref name=Perez2013>{{cite journal |last1= Perez |first1= S.I. |last2= Tejedor |first2= M.F. |display-authors=etal |date= June 2013 |title= Divergence times and the evolutionary radiation of New World monkeys (Platyrrhini, Primates): an analysis of fossil and molecular data |journal= PLOS ONE |volume= 8 |issue= 6 |pages= e68029 |doi= 10.1371/journal.pone.0068029|pmid= 23826358 |pmc= 3694915 |bibcode= 2013PLoSO...868029P |doi-access= free }}</ref>{{Request quotation|date=October 2024}} The individual species of Old World monkey are more closely related to each other than to apes or any other grouping, with a common ancestor around 14 million years ago.<ref>{{cite book |url=https://books.google.com/books?id=rR9XPnaqvCMC&pg=PA138 |page=138 |last=Dawkins |first=Richard |title=The Ancestor's Tale: A Pilgrimage to the Dawn of Evolution |year=2004 |publisher=Houghton Mifflin Harcourt|isbn=9780618619160 }}</ref>

The smallest Old World monkey is the [[talapoin]], with a head and body {{convert|34|–|37|cm}} in length, and weighing between {{convert|0.7|and|1.3|kg}}. The largest is the male mandrill,  around {{convert|70|cm}} in length, and weighing up to {{convert|50|kg}}<ref name="EoM370-405">{{cite book |editor=Macdonald, D. |author1=Brandon-Jones, Douglas |author2=Rowell, Thelma E. |name-list-style=amp |year=1984 |title=The Encyclopedia of Mammals |publisher=Facts on File |location=New York |pages=[https://archive.org/details/encyclopediaofma00mals_0/page/370 370–405] |isbn=0-87196-871-1 |url-access=registration |url=https://archive.org/details/encyclopediaofma00mals_0/page/370 }}</ref> Old World monkeys have a variety of facial features; some have [[snout]]s, some are flat-nosed, and many exhibit coloration. Most have tails, but they are not [[prehensile]].

Old World monkeys are native to Africa and Asia today, inhabiting numerous environments: tropical [[rain forest]]s,  [[savanna]]s, [[shrubland]]s, and mountainous terrain. They inhabited much of Europe in the past; today, the only survivors in Europe are the [[Barbary macaque]]s of [[Gibraltar]]. Whether they were native to Gibraltar or were brought by humans is unknown.

Some Old World monkeys are [[arboreal]], such as the [[colobus]] monkeys; others are [[terrestrial animal|terrestrial]], such as the [[baboon]]s. Most are at least partially [[omnivore|omnivorous]], but all prefer plant matter, which forms the bulk of their diets. Most are highly opportunistic, primarily eating fruit, but also consuming almost any food item available, such as flowers, leaves, bulbs and [[rhizome]]s, insects, snails, small mammals,<ref name="EoM370-405"/> and garbage and handouts from humans.