Pre-history: homo erectus

homo habilis species developed into homo erectus (= person who stands straight, who was around 5.5 feet tall) little more than 2 million years ago. Although they used same material, these early humans developed more sophisticated stone tools; especially evident from their biface (or two sided) stone tools that were ground on both sides. On the defensive side, a revolutionary development was that of building a controlled fire by 1.8 million years ago. This enabled homo erectus to come out of their caves and venture out in open. How? Because, other animals were, and are still afraid of fire. Other side-benefits of fire were: cooking food to sanitize, keeping warm in colder climate, providing light to draw those cave drawings.

Somewhat disputed, but interesting speculation is that these humans also developed rafts to travel over water. Whether they had help from these river or ocean-crossing rafts or not, homo erectus’s historical contribution is that they were the first human family members to leave African continent and venture into Eurasia around 1.2 million years ago. Cause for this migration was drying of African rain forests during the Great Ice Age (Pleistocene). They populated areas as far as France in Europe and Vietnam and China in Asia. Settling in frigid Europe, north Asia and Australia was tougher for this tropical hominids, but most of the Asian continent was welcoming to the new settlers.

With better social organization and technology of tools, homo erectus was hunting with better efficiency than homo habilis. In fact, attaining better efficiency in all skills acquired by their ancestors, was the single most achievement of homo erectus. Otherwise, from hominid development point of view, nothing much happened over a million year or so when homo erectus populated tropical earth.

Pre-history: homo habilis

So, as humans took a different path of evolution from chimpanzees and entered into Old Stone Age (or Paleolithic Era), they were…well…using first stone tools. These were our ancestors of homo habilis (handy person = person with tools of little over 4 feet tall) species about 2.5 to 2.6 million years ago. They were among many other human species. The social experimentation of humans have already begun by this time and they started living in groups. They relied on gathering plants and hunting wild animals to feed themselves. Apart from stone as the primary material for tools, they also used animal bones, wood, leather and vegetable fibers. At this stage, though, large portion of their meat diet came from scavenging from other animal's kills rather than actual hunting.

At this point of evolution, our ancestors were very similar chimpanzees, but subtly different in two defining ways - walking on two legs and depending on tools and other members of their "herd" in addition to their own abilities.