Lucy and her Brain
In 1974, Donald Johnson discovered the first (approximately 4 million years old) fossils of what was know to be an Australopithecus Afarensis. Almost 40 percent of the skeleton was discovered and the remains of the pelvic sector revealed the fossils to be of a female, Australopithecus Afarensis. Today is known to be the famous Lucy.
The discovery showed that Lucy had been fully two-legged but did not have a big brain. Which was again clarified by the fossils found in 1980, by Mary Leakey, of an Australopithecus Afarensis that had nearly identical shape and build. Who also didn’t have a big brain.
Discovery after discovery the idea of a big brain being the theory of evolution in humans became weak and scientist-focused studies towards questioning the earliest survival instincts.
Which of our ancestors could be identified as the earliest human?
Down the evolutionary road to becoming human, the earliest evolution to be two-legged must have been very disadvantageous and dangerous. The two-legged animal cannot match the phase of a four-legged predator’s speed. Surviving and hunting both have an impact on being two-legged and considering injuries in the wild.
It was Leon Festinger, a theorist, and a psychologist, who suggested that it was at this stage that the earliest two-legged ancestors started taking the advantage of the brain. His idea was that through evolution it was this period that they needed to do something about being vulnerable to its own habitat.
“Necessity is the mother of invention”. The necessity to survive and explore must have made our ancestors come closer to form groups that provide safety and company while fighting predators together. The discovery of different types of food among different members of the group could have led to a new nutritional diet, which helps trigger the brain to work even more efficiently.
By this time the idea of the size of the brain is the center of attention has fallen and the brain cells came under the microscopic view.
Neurons are complicating sometimes
From to most recent and accurate discoveries, the Human brain consists of an average of 86 billion neurons. Of these, 69 billion of them are located in the cerebellum. The rest of the 17 billion is located in the cortex the bigger part of the brain and only 1 billion neurons in the rest parts of the brain.
The most surprising fact is that the area of the human brain that is responsible for, picking up sensory information from senses, learning new rules, initiating behavior control, abstract thinking, cognitive flexibility, planning, memory, and many more complex tasks has a lesser neuron percentage supporting its courses.
Most of the neurons are in visual, cerebellum, and other sensory areas and the reason brings more questions.
When the brain size increases with age, the neurons, and their connections with one another increase. And the space between these connections increases with the procedure. The larger the area the better connected it is. But, every neuron does not connect to every other neuron.
As the brain size and its neurons keep increasing, a point occurs where the overall neuron connectivity proportionally decreases, and the internal structure changes. Hence, in order to add new functions to the brain, the proportionally decreased connectivity forces the brain to specialize in certain activities and become automatic in that particular subject.
For example, how we use our limbs? 99% of what we do with our limbs are automatic and most of the time we don’t have to think for our limbs to work.
The result of being automatic is passed and stored in a different part of the brain. But, all the computations, the training level information, and the matrix which helped to arrive at the result are not stored in the brain.
The use of our limbs, we seem to know from the beginning. But none of us understand the math behind how the hand brings food to the mouth even when we are watching television.