Why are our fingers different sizes?
Is the fact that our fingers are in different sizes is related to evolution of man or is there another reason? Although we belong to the primate group such as gorilla, orangutan and chimpanzee, our fingers are a little different from theirs. Here are three different theories about the evolution of human hands.
Our limb, located at the tip of our arm, is our only organ whose name changes according to the purpose it serves. When we use it to hold something, we refer to it as a hand, when we use it for defense purposes, we call it a fist.
In fact, the human hand is quite different from the hands of other primates. Compared to other primates, human fingers and palms are smaller. Our thumb is clearly stronger than our other fingers, and it can easily touch the tip of other fingers. There are three prominent theories about the necessity of our evolution as the different structures and sizes of our fingers.
It is not known exactly when the present form of the human hand first appeared. Primatologists previously estimated that our hands took their present shape 800,000 years ago, but the discovery of the styloid (a protrusion on the bone) of the third scallop bone dating back 1.5 million years changed this estimate. Now the idea prevails that the evolution of the human hand dates back more than 1 million years.
The hands of our ancestors, who lived millions of years ago, were more like the hands of chimpanzees than we have today. Our ancestors’ fingers were longer than their bodies, palms were wider. The thumbs were both weaker and shorter than today.
The fact that the thumb is short is a feature that makes it easy to cling to the tree branches. Our ancestors’ fingers lacked today’s fleshy and tender fingertips and the apical tuft. This structure is generally suitable for holding on to horizontal supports such as tree branches. In this way, it is estimated that our ancestors could easily hold on to the tree branches and swing. But, of course, our hands are much more skillful than our ancestors today.
Studies on the subject have led to the development of different views on the reasons leading to the current structure of our hands. In this article, we will talk about three prominent theories.
Making tools
One of the most popular theories is that structural features, which are more versatile when making tools, have an advantage in survival, so that those who have these features are more successful in transmitting their genes to new generations. For example, having hands that allowed to use axes and similar advanced tools 1.5 million years ago has become an important advantage compared to those who failed. As the tools evolved over time, our hand evolved and reached its present structure. Therefore, it is thought that the advantage of skill plays an important role in evolution.
Clutch
Another theory suggests that our hands evolved depending on the need to gain skill in throwing and holding. Short fingers of different sizes of our hands and small palms have made it easier for us to throw and hold compared to many of the primates. In this work, two different features stand out; The first is the skill we have in catching the ball by bringing our hand to a special position, just like holding the baseball ball; The second is the ability to grasp, for example, thanks to the position and strength of our fingers, especially when holding the handle of an ax.
Defense
When we punch our hand, our fingers can close so that there is no gap in between. What allows this is that our fingers are not of equal length. Our strong thumb makes our fist stronger by hovering over the other four folded fingers, almost locking our hand. Some researchers think that our first weapon, the fist, played an important role in our evolution.
We cannot make a definitive judgment as to which of these factors are more effective and whether there are any other factors that may be important, but we can say that the evolution of our hands and fingers has reached its present form for millions of years.
Source: eksisozluk.com
