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

The hairs were collected and dried. A sample was sent to H. Inagaki in Japan, and
identified by him as belonging to a chimpanzee infant below the age of 3 years. Scale
patterns on the hairs were wavy, and the medulla was rich in granules with the appear-
ance of ants’ eggs (see Fig. 7.1). These characteristics corresponded with those of
chimpanzee hairs previously studied by him (Inagaki and Tsukahara 1993). Our first
evidence that infant eating occurred in the Sonso community was thus circumstantial.
The first events directly indicating that an infanticidal event may have happened at
Sonso were observed and recorded in the Events Book by Zephyr Kiwede on 27–28
December 1993.

On 27 December at 9.40 a.m. Kalema (KL), a subadult female was observed carrying an infant

estimated to be about a month old on her belly. This infant was not hers. The adult male Tinka (TK)

and other adult males chased her, she screamed. The [then] alpha male Magosi (MG) reached her

and displayed by shaking branches. There was much screaming and beating of tree buttresses by

other males. MG pulled KL to the ground and appeared to be trying to get the infant from her. KL

screamed. MG bit her on the face, drawing blood. The infant screamed for the first time. MG was

then seen carrying the infant and running, chased by KL. KL climbed a tree and licked the blood

on her face. A subadult male Zesta (ZT) remained with KL, the other chimpanzees left.

Next day, 28 December, at 9.00 a.m. the adult male Kikunku (KK) was seen carrying the same

infant which was screaming. At 9.30 KK left with the infant. It was never seen again.

Newton-Fisher (1999c) reported on two further cases.
Observed by field assistant Geresomu Muhumuza, on 2 February 1995:

At 7.58 a.m. Geresomu heard some pant grunts and pant hoots and moved towards them. At 8.10 he

found Magosi (MG) sitting on the trail. At 9.00 a.m., he saw the alpha male Duane (DN), sitting close

Infanticide by Sonso males 147

Fig. 7.1: (a) Hair scale patterns and (b) ultrastructure of the medullary cavity of a hair from an
infant chimpanzee (from Bakuneeta et al. 1993).

(a) (b)