Panamanian white-faced capuchin
The Panamanian white-faced capuchin, also known as the Panamanian white-headed capuchin or Central American white-faced capuchin, is a medium-sized New World monkey of the family Cebidae, subfamily Cebinae. Native to the forests of Central America, the white-faced capuchin is important to rainforest ecology for its role in dispersing seeds and pollen.
The Panamanian white-faced capuchin is versatile, living in many different types of forest, and eating many different types of food, including fruit, other plant material, invertebrates, and small vertebrates. It lives in troops that can exceed 20 animals and include both males and females. It is noted for its tool use, including rubbing plants over its body in an apparent use of herbal medicine, and also using tools as weapons and for getting to food. It is a long-lived monkey, with a maximum recorded age of over 54 years.
The white-faced capuchin is a medium-sized monkey, weighing up to. It is mostly black, with a pink face and white on much of the front part of the body, giving it its common name. It has a distinctive prehensile tail that is often carried coiled up and is used to help support the monkey when it is feeding beneath a branch.
Panamanian white-faced capuchins are highly social, living in groups of 16 individuals on average, about three quarters of which are females. Groups consists of related females, immigrant males, and offspring. On average, females birth offspring every 27 months even though they mate throughout the year. Females tend to stay within their original group while males leave their natal group when they are four years old and change groups every four years thereafter. Both male and female capuchins exhibit different dominance behaviors within the group.
In captivity, the Panamanian white-faced capuchin has been used as a companion to the organ grinder. It is an intelligent monkey and has been portrayed as a pet by American media.
Taxonomy
The Panamanian white-faced capuchin is a member of the family Cebidae, the family of New World monkeys containing capuchin monkeys and squirrel monkeys. Until the 21st century, the Panamanian white-faced capuchin was considered conspecific with Cebus capucinus, the Colombian white-faced capuchin, but as a separate subspecies, C. capucinus imitator. Some primatologists continue to consider the Panamanian and Colombian white-faced capuchins as a single species. The Panamanian monkey is a member of the C. capucinus species group within the genus Cebus, which also includes the Colombian white-faced capuchin, white-fronted capuchin, the weeper capuchin and the Kaapori capuchin. This genus is also referred to as "gracile" capuchins.In 2012 a study by Boubli, et al. demonstrated that C. imitator and C. capucinus split up to 2 million years ago. Boubli's study also indicated that the Honduran white-faced capuchins, which had previously been considered a to be a possible separate subspecies, C. capucinus limitaneus, was not genetically distinct from the Panamanian white-faced capuchin.
The Panamanian white-faced capuchin is among the most well-studied capuchin monkey species. Even though many previous studies were performed using the scientific name C. capucinus, as of 2014 there had been no field studies of the Colombian white-faced capuchin, so all these studies were of the Panamanian white-faced capuchin.
Physical description
Like other monkeys in the genus Cebus, the Panamanian white-faced capuchin is named after the order of Capuchin friars - the cowls of these friars closely resemble the monkey's head coloration. The Panamanian white-faced capuchin has mostly black fur, with white to yellow like fur on the neck, throat, chest, shoulders, and upper arms. The face is pink or a white-cream color and may have identifying marks such as dark brows or dark fur patches. An area of black fur on the crown of the head is distinctive. It has a prehensile tail that is often held coiled, giving the white-faced capuchins the nickname "ringtail".Adults reach a length of between, excluding tail, and a weight of up to. The tail is longer than the body, at up to in length. Males are about 27% larger than females. The brain of a white-faced capuchin is about, which is larger than that of several larger monkey species, such as the mantled howler.
The Panamanian white-faced capuchin is similar to the Colombian white-faced capuchin in appearance, except that the female Panamanian white-faced capuchins have brownish or grayish elongated frontal tufts, which provide a contrast to the pure white cheeks and throat.
Behavior
Social structure
The Panamanian white-faced capuchin is a diurnal and arboreal animal. However, it does come down to the ground more often than many other New World monkeys. It moves primarily by walking on all four limbs. Itlives in troops, or groups, of up to 40 monkeys and has a male/female adult sex ratio of 0.71 on average. With rare exceptions, females spend their entire lives with their female kin. Males migrate to new social groups multiple times during the course of their lifetimes, migrating for the first time between 20 months and 11 years of age. The median age of migration in the Santa Rosa population is 4.5 years. Males sometimes migrate alone, but more often they migrate in the company of other males who are often their kin. One of the unusual features of the kinship structure of the Panamanian white-faced capuchin, relative to other primate species, is the high degree of relatedness within groups that results from the long tenures of alpha males who sire most of the offspring. Alpha males have been known to keep their positions as long as 17 years in this species and this puts them in the unusual position of being available to sire the offspring of their daughters and granddaughters, who produce their first offspring at about 6–7 years of age. Typically, however, alpha males do not breed with their own daughters, even though they do sire virtually all offspring produced by females unrelated to them. Those subordinate males who are allies of the alpha male in group defense are the males who sire the offspring of the alpha male's daughters. The high degree to which alpha males monopolize matings results in an unusually large number of paternal half-siblings and full siblings in this species relative to other primate species.
Kinship is an important organizing factor in the structuring of female-female social relationships. Particularly in larger groups, females preferentially associate with, groom, and provide coalitionary support to their matrilineally related female kin. They do not exhibit a similar preference for their paternal half sisters, which may mean that they only are capable of recognizing kinship through the maternal line. Dominance rank is also an important organizing factor, with females more often grooming and associating with females who are closer to them in the dominance hierarchy. Female-female dyads groom far more than male-female and male-male dyads. Coalitionary aggression is common both among males and females, and capuchins seem to have an excellent understanding of the alliance structure in their group. For example, when capuchins are fighting, they sensibly recruit aid from someone who is both higher ranking than they are and also better friends with themselves than with their opponent.
Female capuchins have linear dominance hierarchies. In contrast to many Old World monkeys such as macaques, in which females socially inherit the rank just below their mothers and just above their next oldest sisters, capuchins do not have a highly predictable ranking within their matrilines. Males are typically dominant to females. The alpha male is always easy to discern, but there are sometimes ambiguous rankings among subordinate males. Male-male relationships are tense, and affiliation between males is typically expressed by resting in contact, playing, or non-conceptive sex rather than by grooming. Males cooperate in coalitions against potential predators, and also in defense of the group against other males. Occasionally male coalitionary aggression becomes so violent that males are killed, particularly if they are encountered roaming the forest unaccompanied by allies. Because aggression from other male capuchins is the leading cause of death, male allies are critical for self-defense during migration, and to assist in taking over other groups. Male emigration to a new troop typically occurs about every 4 years, so most males are in constant danger of having to defend themselves against other groups of males.
Immigrating males often kill young infants when they take over a group. Females band together to defend their infants from infanticidal males, but they rarely succeed in saving their infants. Because infants inhibit their mothers from ovulating by nursing frequently, males are able to bring females into estrus earlier by killing the infants and thereby terminating nursing; this has the effect of increasing their breeding opportunities. Females do often mate with the killers of their infants, and with time, they typically become as supportive of the new alpha male as they had been of the previous one. The alpha male helps defend females from subordinate males within the group as well as from infanticidal males from other groups.
Interactions between groups
Panamanian white-faced capuchin troops occupy home ranges of between. They travel between daily, averaging per day. Although they engage in activity that has been described as "territorial", more recent research indicates that white-faced capuchin troops tend to behave aggressively to other white-faced capuchin troops regardless of where they meet, and the aggression is not necessarily intended to exclude the other troops from a specific home range.Home ranges overlap extensively, so groups are not territorial in the strictest sense of the word. Perhaps because of the intensity of male-male competition and the threat of infanticide, interactions between groups are typically hostile: the males display aggressively toward one another and sometimes engage in physical aggression, while females grab their infants and run. Typically, males are the primary participants in aggressive intergroup encounters, and it seems likely that males are defending access to the females in their groups. Alpha males, who have the largest reproductive stake in the group, participate at a higher rate than subordinate males. Groups with more males have an advantage over groups with fewer males, but the location of the encounter within the home range matters as well; smaller groups defeat larger groups when the contest occurs in the core or center area of the smaller group's home range.