The researchers have conducted a study that offers vital clues about the evolution of chimpanzees and their mating behavior. The study has showed that the aggressive male chimps are more sexually active and successful mating partners than their gentle counterparts.
The report, by the experts at the Arizona State University, showed that the aggressive male chimps often attack females (causing injuries that may be fatal in nature) as a sexual coercion technique and entered into mating more often than the gentlemen.
The researchers carried a long period observational study for as much as 17 years at the Gombe National Park. The animals considered for the study belonged to the Kasekala chimpanzee community. For the study, the group also collected DNA from fecal matter of the species so as to find the paternity of as many as 31 infants. Moreover, the experiment would also help the scientists to find out which individual males were most successful in their sexual activity.
Such type of aggressiveness was found effective among the high-ranking animals in the chimp hierarchy, said Ian Gilby, from Social Change and Arizona State University the School of Human Evolution.
Researchers say this unpleasant behavior was noticed as a very frequent occurrence among chimpanzees in the East African field sites.
Gilby said males generally used such violent tactics to have a long-term sexual intimidation with the females and keep the other males away from their mating partners.
They were, moreover, dominating over female chimpanzees even when there was no mating season. Instead the males were seen mating more often than usual.
Some male chimps were also witnessed of being engaged in killing the offspring of their mating partners. This was done most probably in an attempt to finish the competition among males and keep the females busy in the mating act with themselves and also keep the young ones away from their mothers.
But the female chimpanzees defeated such behaviour by mating with other males of the group. This act used to spread confusion among the males about their own young ones and hence they avoided killing any.
The study has been detailed in the US journal Current Biology.