The Hand - Grasping Evolution Of Man
It is our hand that made our evolution into Homo Sapiens, into the humans we are today, possible. Anthropologists and evolutionary biologists have provided conclusive evidence in recent decades: The development of our brain, of our thinking, was also primarily promoted by the hand.
The human brain only developed further after hominins had learned to use tools more and more skillfully. Millions of years ago, our ancestors began to use their hands for more than just locomotion. They were able to use stones for hammering, for example. The hands absorbed the heavy loads and cushioned them. The starting point for these uses was the thumb. The thumbs of hominins were already longer than those of orangutans, gorillas and chimpanzees. This gave them three grips that formed the basis for further development:
The lateral pincer grip: The tip of the thumb presses against the side of the index finger.
The 3-point grip: thumb, index finger and middle finger grip an object.
The 5-point basket grip: All five fingers hold the object - and the object can be moved simultaneously with all five fingers.
By modifying the hominins' hands, it was possible to throw stones, throwing axes and targets with precision. For the first hunters, precision throwing proved to be a survival factor. Those who could throw better were able to catch more prey and feed themselves better. As a result, they remained more productive and reproductive.
Scientists assume that the increasingly sophisticated ability to throw accurately caused the brain to grow. This is because accurate throwing created a huge demand for more and more nerve cells firing together.
Picking up a hammer, aiming it precisely and then throwing it is a huge physiological challenge. To be able to throw accurately, the ability to create a target image is essential. The movements required to hit this target are then calculated. Next, the coordination of movement between the hand, arm and shoulder and the movement of the whole body is developed. The arm is tensed together with the whole body during the lunge. As with a catapult, the body creates the tension so that rapid acceleration of the hand is possible. At the same time, the thrown object is released at the right moment.
Our ancestors thus developed a forward-looking coordination between time, space and effort in the body through throwing while hunting, which required more and more neuronal connections. Scientists suspect that the relatively rapid increase in brain volume of our ancestors was significantly influenced by this.
Throwing and the more complex brain structures associated with it have subsequently made other typically human abilities possible. For example, human language is dependent on the highly precise sequencing of movement. The changes to our brains made possible by precise throwing have also created the basis for human language.
Conclusion: It is our hand that made our evolution into Homo Sapiens, into the humans we are today, possible. If you would like to read more about this, I recommend the following books:
Wilson, F.: The hand - a stroke of evolutionary genius. Its influence on the human brain, language and culture. Klett-Cotta, Stuttgart 2000.
Calvin, W. H.: The stream that flows uphill. A journey through evolution. dtv, Munich 1997.
