Editing Semnopithecus (section)

===Reproduction and parenting===
[[File:Semnopithecus priam.jpg|thumb|Tufted gray langur with young]]
[[File:GrayLangurWithNewBorn1.JPG|thumb|Gray langur with newborn]]
In one-male groups, the resident male is usually the sole breeder of the females and sires all the young. In multiple-male groups, the highest-ranking male fathers most of the offspring, followed by the next-ranking males and even outside males will father young.<ref name=r11/> Higher-ranking females are more reproductively successful than lower-ranking ones.<ref name="Borries 1991"/>

Female gray langurs do not make it obvious that they are in [[estrous]]. However, males are still somehow able to deduce the reproduction state of females.<ref name=r12/> Females signal that they are ready to mate by shuddering the head, lowering the tail, and presenting their anogenital regions.<ref name="Sommer 1992"/> Such solicitations do not always lead to copulation. When langurs mate, they are sometimes disrupted by other group members.<ref name="Newton 1987"/> Female langurs have been recorded mounting other females.<ref name=b1/>

The [[gestation]] period of gray langur lasts around 200 days, at least at Jodhpur, India. In some areas, reproduction is year-around.<ref name="Sommer 1992"/> Year-round reproduction appears to occur in populations that capitalize on human-made foods. Other populations have seasonal reproduction.<ref name="Newton 1987"/>
[[Infanticide (zoology)|Infanticide]] is common among gray langurs. Most infanticidal langurs are males that have recently immigrated to a group and driven out the prior male. These males only kill infants that are not their own.<ref name=b2/> Infanticide is more commonly reported in one-male groups, perhaps because one male monopolizing matings drives the evolution of this trait. In multiple-male groups, the costs for infanticidal males are likely to be high as the other males may protect the infants and they can't ensure that they'll sire young with other males around. Nevertheless, infanticide does occur in these groups, and is suggested that such practices serve to return a female to estrous and gain the opportunity to mate.<ref name="Borries 1997"/>

Females usually give birth to a single infant, although twins do occur. Most births occur during the night.<ref name="Agoramoorthy 1992"/> Infants are born with thin, dark brown or black hair and pale skin. Infants spend their first week attached to their mothers' chests and mostly just suckle or sleep.<ref name="Sugiyama 1965"/> They do not move much in terms of locomotion for the first two weeks of their life. As they approach their sixth week of life, infants vocalize more.<ref name=r13/> They use squeaks and shrieks to communicate stress. In the following months, the infants are capable of quadrupedal locomotion and can walk, run and jump by the second and third months. [[Alloparenting]] occurs among langurs, starting when the infants reach two years of age. The infant will be given to the other females of the group. However, if the mother dies, the infant usually follows.<ref name="Sugiyama 1965"/> Langurs are weaned by 13 months.