The Evolution of the Human Capacity for 'Killing at a Distance'

Richard Rathe, December 2010 (Technology)

Anthropologists Steven Churchill & Jill Rhodes recently wrote a fascinating article on the development of projectile weapons by early Homo sapiens and subsequent effects on large carnivores (extinction!) and human evolution.

Their basic premise is that sometime in the past 250,000 years humans discovered how to kill at a distance. This allowed us to crowd-out the various carnivore gilds including our co-evolved cousins the Neanderthals. In this photo he holds a thrown projectile weapon (light spear with atlatl) in his right hand and a reproduction of a Neanderthal thrusting spear in his left.

These weapons have also had a profound effect on modern human conflicts. When we fight with thrusting weapons, the probability of injury is a linear function of the number of combatants: 0.5 with two on one, 0.33 with three on one, 0.25 with four on one, etc. So the strategy is to bring lots of friends to a fight! With projectile weapons and the function becomes exponential with the probability of injury decreasing by the square: 0.25 with two on one, 0.11 with three on one, and 0.06 with four to one!