Chalk up another one for Charles Darwin, for scientists now actually can prove their point: species do evolve and adapt against harsh environments. The chimpanzee, regarded as the human's closest link down the evolutionary chain, used a primitive form of a spear to hunt bush babies (nagapies).

While observing the Fongoli chimpanzees of southeastern Senegal, Jill Pruetz and Paco Bertolani of Iowa State University also noticed that only the females created spears and used them to hunt.

Bertolani claims to have seen an adolescent female chimpanzee select a branch, strip off the twigs and leaves, and chew one end into a sharp point.

With the rather unimpressive spear, the chimpanzee would then poke holes in places where they believe the nagapies could be hiding. They only were able to observe a successful kill once.

Though it may look to be just a fluke of nature, Pruetz claimed to have seen it happen repeatedly over the course of 19 days. Because only the females use the spears, Pruetz believes that the males depend on their physical strength to hunt and gather for food. She believes that perhaps females were originally the ones who invented weapons for hunting.

She continues to conclude her findings:

The observation that individuals hunting with tools include females and immature chimpanzees suggests that we should rethink traditional explanations for the evolution of such behavior in our own lineage. The multiple steps taken by Fongoli chimpanzees in making tools to dispatch mammalian prey involve the kind of foresight and intellectual complexity that most likely typified early human relatives.