|
|
|
Title: How social hierarchies differ between Theropithecus Gelada (Gelada Baboon) and Mandrillus Sphinx (Mandrill) society?
Author: Aaron Wheatley
Establishment: Copleston High School, A2 level biology
Summary: This study was conducted at Colchester Zoo, and was targeted on the gelada baboon group consisting of six individuals and twenty-three strong troop of Mandrills, of which just six were observed. The six mandrill individuals observed were one alpha male, one dominant female who is currently mothering an infant, one sexually active female, a young adult female, one female infant and also one male infant. These individuals were chosen due to their similar status to the individuals within the gelada group. The aim of the study was:
• To investigate whether the social hierarchies of both Gelada and Mandrill differ and to what extent they differ
• To investigate the role of the Alpha Male, and to what extent his own individual behaviour influences the troops general routine and behaviour
A data statistics table was used to identify and record any grooming interactions between group members, communication methods and also evidence of kinship within each troop. An individual interaction table was also used, which helped to identify which individual was interacting with who, and also the frequencies at which the interactions were occurring.
Complete article:
From observing both species and analysing the results, it is evident that a difference does exist between the Gelada Baboon and Mandrill species concerning grooming behaviours. The differences lay between both the total amount of grooming interactions and also the time of day in which most grooming interactions occurred within. Collectively and individually, each Gelada was either subjected to, or participated in a grooming interaction at a much more frequent rate than that of the individuals within the Mandrill troop. Also, a difference was seen in the timings of grooming. For the geladas, there was a negative correlation when categorising the amount of grooming interactions with a specific time of day; the later in the day, the less grooming interactions observed. The Mandrills did not seem to follow such a regimental regime of grooming and grooming did not seem to take place according to a time scale.
The observations made concerning the vocalizations/gestural communications of each group were as expected, in that the Alpha Male of each group was highly vocal throughout the day. The alpha male gelada had a higher rate of vocalization compared to the mandrill, but despite the alpha male mandrills lack of vocalization, he appeared to assert his dominance in a more aggressive nature, rather than vocalise. The time of day did not play a part in what and if a vocalisation was used for either species.
As a group, the individual interactions were much higher within the Gelada troop than that of the Mandrill troop. The Geladas demonstrated frequent interactions with each other, mainly the two youngest individuals whom were highly playful with each other, and so therefore interacted with each other at a higher rate. As a whole, it was clear to see that the individuals that occupy the Gelada troop are of a more social nature, but despite this, from observations, it was clear to see that Dumé, the alpha mandrill male, was in fact more sociable on an individual level with his group than the alpha gelada was within the Gelada troop.
|
|
|
|
