As mentioned in the first part, the Controlling Instinct model posits the existence of a basic instinct that bridges the gap between animal instinct (DNA engraved instincts) and human instincts (brain evolved instincts). This instinct facilitates the development of advanced cognitive powers characteristics of humans. In the evolution ladder, this instinct appeared with the a specific hominoid species that resulted in the emergence of the sapiens.
Does science support this position?
Anthropological Perspective
In anthropology, there is ample evidence that something happened, few hundred thousand years ago, that developed the brain of the homo species which resulted in the emergence of the thinking species. Most theories attributes this jump to the discovery of cooking by fire. Eating cooked food, especially meat, helped divert most of the digestion energy to the other organs of the body especially the brain. Providing such increased energy to the brain allowed it to create a bigger organ that was able to develop new synapses other species do not have. The brain has the ability to develop beyond the norm.
However, this sudden supply of energy did not create the qalam, that is the ability to develop knowledge and dynamic cognitive powers. Another factor had to play a complementary role. This factor is the premature delivery of babies, compared to other species. Homo sapien’s brain continue it development outside the womb while all other species are born with almost matured brain. Harari calls this “homo sapiens are born with half baked brain”. This means the brain continues growing and developing following triggers by sensory observations and experiences of the real world.
Here is the explanation. The increased size of the brain created a problem and a solution. The female hominoids with an evolved DNA responsible for the enlarged brain could not deliver the mature fetus because their womb and cervix could not handle the passage of such enlarged and advanced partially developed brain like other species. As anthropologists puts it, most mother died upon delivery, few weaker mothers dropped their fetus prematurely. Few of these premature babies survived but they needed to complete the development of their brain outside the womb. Neurologists, as will be presented in the next section, say that the complete development of the brain takes around 3 years after birth to form the necessary neurons and the interconnecting sybapses. This means, the brain was growing and being developed while the baby/toddler is experiencing real life interactions through their 6 senses (5 being the known senses while the 6th is the emotional experience). This interaction at such an early stage allowed the brain to create new synapses that other species did not posses. One outcome of this evolutionary development is having a superior plasticity of the brain that let it grow based on sensual experiences at a level no other species could achieve. This is the qalam.
So, in anthropology, there are ample evidence that something happened that shifted a specific species from being owners of slow developing brain to incredibly flexible and adaptable brain that continuously change based on sensual incentive.
Next, neuroscience perspective.
Related References
Harari, Yuval Noah; Vintage (2014). Sapiens: A Brief History of Humankind.
Wolpoff, M. H.; Spuhler, J. N.; Smith, F. H.; Radovcic, J.; Pope, G.; Frayer, D. W.; Eckhardt, R.; Clark, G. (1988). “Modern Human Origins”. Science. 241 (4867): 772–74.