We Eukaryotes

Part 12 - Technology

Between 120,000 and 50,000 years ago our ancestors were still hunter-gatherers but they were wearing clothing and jewellery and using pigment to draw symbols and rituals for burials. They were still living in temporary shelters, or caves, indicated by the oldest known cave art.

They were inventing new tools such as fishing nets, hooks, and bone harpoons and consuming a larger variety of food. They were using more elaborate techniques to kill larger animals and slowly devising ways to improve the chance of survival but they were still using stone tools. They lived in family groups of perhaps twenty to thirty individuals and defended a territory large enough to provide food for the group. The head of the family was typically the father and in larger groups there was inevitably strife as people tried to dominate others. Justice was rough. Individuals guilty of offending the group or the head of the family were beaten, killed or banished.

The development of language must have been influenced by the love of story telling. We can imaging people sitting around a camp fire after dark avidly listening to someone telling tales of adventure. These were probably about hunters killing large animals and heroic exploits during border raids or incursions into hostile territory to steal women. But there were also cautionary tales about children attacked by hyenas if they wandered too far away from adults. And humour must have embellished any successful story.

Story telling and humour evolved as survival techniques because they made people feel pleasure in the presence of others while also educating the young about food sources, hunting techniques and self preservation. And people who lacked a sense of humour were generally less attractive as sexual partners.

Populations grew slowly. The average lifespan was probably around 40 years mainly because of the high death rate of children at birth, or within the first five years, from disabilities, infections and predators. Only the toughest and luckiest survived.

In good times there were more births than deaths but the population was quickly reduced by plagues and starvation caused by drought. Although there was normally little interaction with other groups except in border skirmishes, people fleeing from areas affected by plague effectively spread lethal viral or bacterial organisms from group to group. The family might split up if it became too large for the local food supply and this might required a hostile invasion of neighbouring territory.

After the discovery of the spear and the simple hand axe, hunter gatherers slowly added more tools to their possessions. Two of the first were probably the wedge and the lever.

The wedges were made of bone, horn, wood or stone. A small wedge shaped, chipped stone could be used as a spear point and a larger hand axe would split or trim logs or animal carcasses. Wooden wedges could be hammered into a split tree trunk and would swell after being saturated with water.

At least 200,000 years ago men found that they could lift a rock heavier than themselves by jamming a tree branch lever under the rock, placing a stone under the branch near the rock, as a fulcrum, and using their weight to push down on the other end of the branch. The rock could be lifted higher, or moved sideways, by lowering the rock onto smaller stones placed underneath while repositioning the lever and fulcrum, or by using two or more levers.