US tab

Background

The Lesser Spot Nosed Guenon belongs to the Cercopithcinae subfamily. This subfamily is defined as old world monkeys found within Sub-Saharan Africa characterized by a simple stomach and the presence of cheek pouches used to temporarily store food. These pouches can hold the equivalent of a stomach load of food and have been observed to be used to hoard food from conspecifics (Buzzard 2006). This adaptation benefits the individual since the use of cheek pouches significantly reduces time spent in areas of high competition or predation risk. The Cercopithcinae subfamily shares an omnivorous diet consisting of fruit, insects, and leaves. When foraging, groups of Cercopithcinae assume a dispersed spacial positioning with the most profitable positions being at the edge of the group. Dominant individuals are often seen claiming the densest food patches and defending them from less dominant members of the group (Hirsch 2007). Another trait of the Cercopithcinae subfamily is a high degree of sexual dimorphism. In the case of C. petaurista, females weigh 66% less than their male counterparts (Kingdon 2003).

C. petaurista or Lesser Spot-Nosed Guenon is defined by the large white spot on this species' nose. C. petaurista is generally 0.91 to 1.22 m long and weighing 2.72-3.62 kg on average (Central Florida Zoo). The lifespan of this species is around 20-30 years in length. There are two subspecies of C. petaurista isolated by a river that splits the territory the species occupies along the coast of Western sub-Saharan Africa. (Kingdon 2003). Within this territory, this species can be found in terrestrial ecosystems such as primary forests, secondary forests, farm clearings, and successional forests. It is diurnal and moves quadrapedally through the lower strata of the forest canopy in its natural habitat (Central Florida Zoo). Mating within communities of C. petaurista is polygamous with communities consisting of anywhere from 10-40 individuals. Sometimes, these groups can be interspecific among other species of Cercopithecus (San Diego Zoo). Females have been observed to engage in "presenting" to display to males their sexual receptivity. Presenting behavior is a visual signal communicated when an individual raises their posterior in the air towards another individual. It can also be used as a greeting or submissive display (Morris 2006). Mothers typically give birth to and care for one infant. Cooperative breeding, a form of parental care where individuals that are not directly related to offspring aid in rearing them, is commonly seen in this species among the females of a community. Natal dispersal is often seen in the wild when male youth reach adolescence. These males will either become the head of their own communities or become a roaming male. Roaming males can either live in solitude or as a part of a bachelor group (Central Florida Zoo).

Figure 1: Social Grooming observed in C. petarurista.

As a highly social species, communication is complex and highly developed among C. petaurista. This species is mostly reliant on visual communication through complex head movements. The importance of this mode of communication can be seen through the adaptation of the white spotted nose, which allows this species to visualize head movements across a distance in their forest habitat (Zoo Miami 2017). Facial expressions and posture are also used as a form of visual communication. They are often incorporated into agonistic threat displays in the forms of bared teeth, an open mouth, and staring with raised brows (Morris 2006). Auditory communication is also present among this species through chirping and sneeze-like vocalizations. The sneeze call is used as an alarm call to alert conspecifics about the presence of aerial predators. A purring alarm call has also been observed among C. petaurista to distract predators, thus facilitating the escape and survival of other community members (San Diego Zoo).

As a primate, social grooming, as seen in Figure 1, is another key aspect of social dynamics within C. petaurista. Grooming in wild populations has been observed to be linked to social status. In his paper, Robert Seyfarth models this dynamic based on wild social groups of old world monkeys. According to the Seyfarth model, female members of adjacent ranks within a social hierarchy are the most likely pair to be grooming partners due to a desire to groom those who hold a higher social status to gain access to some of their privileges. Grooming with top ranking partners is limited by competition with other members of a group for these high-ranking grooming partners (Seyfarth 1977).

Methods >>