Editing Proboscis monkey (section)

===Reproduction===
Females become sexually mature at the age of five years. They experience [[sexual swelling]], which involves the genitals becoming pink or reddened.<ref name=Murai2004/><ref name=Murai2006/>  At one site, matings largely take place between February and November, while births occur between March and May.<ref name=Rajanathan1990>{{cite journal|author1=Rajanathan R. |author2=Bennett E. L. |year=1990| title=Notes on the social behaviour of wild proboscis monkeys (''Nasalis larvatus'')| journal=Malay Nat. Journal |volume= 44| issue=1|pages=35–44}}</ref> Copulations tend to last for half a minute.<ref name=Boonratana1993/><ref name=Murai2004/>  The male will grab the female by the ankles or torso and mount her from behind.<ref name=Boonratana1993/> Both sexes will encourage mating, but they are not always successful.<ref name=Murai2006>{{cite journal|author=Murai T.|year=2006| title=Mating behaviors of the proboscis monkey (''Nasalis larvatus'')| journal=American Journal of Primatology | volume= 68| issue=8|pages=832–837 |doi=10.1002/ajp.20266|pmid=16847976|s2cid=10625574}}</ref>  When soliciting, both sexes will make pouted faces. In addition, males will sometimes vocalize and females will present their backsides and shake their head from side to side.<ref name=Bennett1993/><ref name=Murai2006/><ref name=Rajanathan1990/><ref name=":0" /> Mating pairs are sometimes harassed by subadults.<ref name=Murai2006/> Proboscis monkeys may also engage in mounting with no reproductive purpose, such as playful and same-sex mounting, and females will attempt to initiate copulation even after they have conceived.<ref name=":0" /> Gestation usually last 166–200 days or slightly more.<ref name=Rajanathan1990/> Females tend to give birth at night or in the early morning. The mothers then eat the placenta and lick their infants clean.<ref name=Gorzitze1996>{{cite journal|author=Gorzitze A. B.|year=1996| title=Birth-related behavior in wild proboscis monkeys (''Nasalis larvatus'')| journal=Primates| volume= 37| issue=1|pages=75–78 |doi=10.1007/BF02382922 |s2cid=39403318}}</ref> The young begin to eat solid foods at six weeks and are weaned at seven months old. The nose of a young male grows slowly until reaching adulthood. The mother will allow other members of her group to hold her infant.<ref name=Boonratana1993/><ref name=Rajanathan1990/><ref name=Gorzitze1996/> When a resident male in a one-male group is replaced, the infants are at risk of infanticide.<ref>{{cite journal|author1=Agoramoorthy G. |author2=Hsu M. J. |year=2004| title=Occurrence of infanticide among wild proboscis monkeys (''Nasalis larvatus'') in Sabah, Northern Borneo| journal=Folia Primatol.| volume= 76| issue=3|pages=177–179 |doi=10.1159/000084380 |pmid=15900105|s2cid=20111145}}</ref>