288 Self and the Phenomenon of Life
b2726 Self and the Phenomenon of Life: A Biologist Examines Life from Molecules to Humanity “9x6”lived peacefully most of the time, but once every ten days, a band of
males (up to twenty) would silently form a single file and cautiously
patrol the border of their established territory. While doing this, the
patrolling troop looked for males of the rival camp in the neighboring
area. If the group was clearly out numbered, it would immediately dis-
band and hurry back to its home turf. But if the soldiers encountered
a lone male, they would kill it. The killing incidents were observed at
least eighteen times over a period of ten years. Interestingly, most of
the patrols occurred in an area to the northeast of their territory. After
a decade-long “campaign,” the Ngogo chimpanzees eventually annexed
this new region, thereby expanding their territory by 22%, a definite
selective advantage as they now had access to more food resources. The
success of territorial expansion was an outcome of not only intergroup
competition and aggression, but also internal cooperation and cohesion,
being able to hold an unusually large community of 150 members (three
times the usual size). What is biologically interesting is that, despite
inter-group hostility, there was constant genetic blending between the
rival communities (by grabbing each other’s females), suggesting that in
this instance group selection and not kin selection was at work.
12.13.3 Rwandan massacre
In Rwanda in the year 1994, the Hutu tribe committed genocide against
Tutsi, killing approximately 800,000 in a hundred days. Both groups were
Christians and they spoke the same language. The historical background
is that, before Rwanda’s independence, the Belgian colonists favored Tutsi
as the superior tribe, using it to rule over the majority Hutu. Because of
their superior position, the Tutsi were rich, whereas the Hutu were poor.
On the other hand, the Hutu despised and hated the Tutsi and viewed
them as foreign invaders who came to the land generations earlier. After
independence in 1962, the power shifted from Tutsi to Hutu.
In April of 1994, extremist Hutu militia and elements of the Rwanda
military decided to exterminate the Tutsi. The militia set up road blocks