For example, when primitive man shifted from hunting small animals to big game hunting, this change required new skills in planning, in leadership, and in communication- and this created selection pressure for the development of these capacities.
(primitive man; shifted; from hunting small animals to big game hunting) (this change; required; new skills in planning; T:when primitive man shifted from hunting small animals to big game hunting)
primitive man this change
shifted required
from hunting small animals to big game hunting
new skills in planning T:when primitive man shifted from hunting small animals to big game hunting