Groningen researchers make interesting discovery about monkey behavior
23 Jul 2008
Researchers at the University of Groningen recently discovered that female monkeys are more dominant when they live in groups with a higher percentage of males.
What makes the study particularly interesting is that the researchers used a computer model which can simulate interaction between monkeys. Their findings were published on July 16 in the journal Plos One.
Many animals living in groups have a social hierarchy, a so-called ‘pecking order’. Monkeys, too, have a social hierarchy. Highest in the pecking order is the most dominant monkey, who consistently wins aggressive interactions (such as biting) with other group members. At the bottom of the hierarchy is the lowest ranking monkey, who consistently loses interactions with other members of the group. Monkeys have to fight for their place in this hierarchy every day.
Simulation
The position of females in the hierarchy varies among different monkey species. In most species females are ranking below the males. This is no wonder, because they are usually much smaller than males. However, in the case of the Lemur species of Madagascar the females are dominant, in bonobos, males and females roughly equal each other in dominance, and among a lot of other species (macaques and the grivet, for instance) females are weakly dominant (this means that the most dominant females rank above approximately a third of the males).
‘Until now, it was unknown how this female dominance develops’, says Charlotte Hemelrijk, theoretical biologist at the University of Groningen and the first author of the article which she wrote together with Dr. Jan Wantia and a Swiss anthropologist, Dr. Karin Isler. Researchers in Groningen therefore created a virtual world, Domworld, with which they could simulate the interactions between monkeys.
Source: University of Groningen
Read the entire press release (which also contains a link to the full article).