Chimpanzees of the Budongo Forest : Ecology, Behaviour, and Conservation

of the Sonso community. (And so it should have been, for as it turned out when we later
did our genetic analysis of paternity (see Appendix C), he was the father of many of the
next generation.)

How to defeat an aggressive challenger

MG lost his alpha position in 1995 (he had been the alpha male since the start of our
studies, and probably for many years before) as a result of a direct challenge by DN. We
did not have anyone studying in detail how MG held off the challenge of DN, and
possibly challenges by other males, before he lost power, but he did associate fairly
closely with BK. From 1998 to 1999 there was a second study of our adult males by
Arnold (2001) and this was followed by a third, shorter study in mid-1999 by Dempsey
(2000). These studies shed light on how DN defeated a challenge by an aggressive male,
BK, and also how he safeguarded his position afterwards. These details make a fascin-
ating story and show how complex and, in a way, brilliant, adult male chimpanzees can
be in the political arena around them.

128 Social behaviour and relationships

ZTZF

TKAY

MUJM

CHBK

MANJ

BYKK

VNDN

MG

1.0 0.5 0.0

QTR1: 1/95 – 3/95

ZTZF

JMBK

MGTK

CHAY

BYNJ

MUKK

VNDN

MA

1.0 0.5 0.0

QTR2: 4/95 – 6/95

JMTK

NJ

BKZF

CHZT

AY

MUBY

MGKK

VN

MADN

1.0 0.5 0.0

QTR3: 7/95 –10/95

CHZF

JMNJ

MUAY

BKZT

KKTK

MGBY

MAVN

DN

1.0 0.5 0.0

QTR4: 11/95 –12/95

Fig. 6.7: Dendrograms showing the results of cluster analysis of male–male dyadic associations
for each quarter of 1995 (from Newton-Fisher 1997).