In one case, Frodo was the largest of the three chimps. His maximum weight was 51.2 kilograms.
However, in another case, the smallest of the chimps, Wilkie, used grooming as an aggressive tactic to become the group’s alpha male from 1989 to 1992.
At only a weight of 37 kilograms, Wilkie used excessive grooming to win over friends. He spent much of his time grooming others; especially his female partners.
Most alpha males do not groom other chimps, and only receive grooming from their mates.
In the third case, the second-largest chimp, Freud, weighed 44.8 kilograms at its maximum. He displayed a combination of mild aggression and mild grooming to attain the alpha-male position, which he held from 1993 to 1997.
Dr. Foster, one of the authors of the study, stated, “It's kind of like when I was a teenager and the football team's quarterback lost the school's popularity poll to a wimpy, unassuming fellow who was also quick-witted. The latter fellow was able to make friends through his sense of humour and charisma, and in turn achieved a kind of alpha status over the brutish quarterback.” [Nature News: “Grooming your way to the top”]
U.S. primatologist Elisabeth Lonsdorf (Lincoln Park Zoo, Chicago, Illinois), who was not part of the study, stated, “This is fascinating and finally begins to quantify different strategies for attaining alpha status in males, which I don't think we've understood very well in the past.” [Nature News]
Lonsdorf added, "In my experience, no two alpha males at Gombe National Park have ever used the same strategy. Some have appeared more violent, some more friendly. One learned to use tin cans to scare the bejesus out of everybody. This research is opening the door so we can further investigate and finally quantify all of these differences that we are seeing." [Nature News]