While the exact origin of consciousness is debatable, and polarized on a mammalian time-chart, the fact that all mammalian creatures acquired consciousness as a datum, that is, as a fixed starting point in our brains, is not.The history of these living, yet mortal, creatures is documented by their fossils that are preserved in sedimentary layers over geologic time, where we can see (read) the small patterns to help understand the big picture, and that, is the progression of evolution. Yet, there are at least two types of mammalian evolution.
The first and most obvious is the aforesaid fossil record. That record, despite gaps, is of such an exacting nature that it is no longer considered a theory of evolution, but the established fact of evolution.
The second, though less understood and even less talked about in general company, is mental evolution. All of us mammalian cousins undergo mental evolution which is more akin to rapid progression, unlike the fossil record which is slow, taking place over eons. Mental evolution, particularly in humans, can happen over generations and possibly in minutes or seconds.
It was nearly a half a billion years ago when early vertebrates evolved brain symmetries. This ancient “backbone” society of warm-blooded living things was the antecedents of all living mammals, including Homo sapiens sapiens, which comprises all modern races of people.
Since mammals are bilateral organisms, we are essentially split into two side by side parts, including the brain. Aside from the obvious symmetry of our two eyes, two ears, two legs, etc., evidence of human cell division fusion during the fetal developmental continuum is often clearly evidenced in the perineum where a visible ridge or line runs from the anus to the scrotum or vulva.
When anatomically modern humans emerged in central Africa about 200, 000 years ago you might have difficulty distinguishing them from your neighbors today. Since mental evolution, however, takes place within our brains the difference between the human mind 200,000 years ago and now is worlds apart, despite our body and brain being relatively the same size.
It is because of the “apparently sudden evolutionary appearance” of the corpus callosum, as well as the “lack of any identifiable (similar) precursor structure in nonplacental species,” that the corpus callosum in mammal brains has been described as “a true evolutionary novelty.” Previously all mammals had been mentally working with a split brain. But then the rather abrupt appearance of this “major inter- hemispheric fibre bundle tract in the brain of placental mammals” changed us all forever:
Consciousness was born.
Because the corpus callosum is not found in nonplacental species its origin and therefore consciousness itself is clearly anchored in mammalian (placental) animals. Moreover, by establishing that the causal agent of consciousness is the result of Earth’s evolutionary processes, all that makes consciousness what it is and what it means is noteworthy, in-that, without scientific proof there is no reason to assume it exists anywhere off of our planet. And, any attempts to enlarge consciousness to a universal status is speculation only and not justifiable.
The ramifications for localizing consciousness to this particular planet, and specifically in mammals, is primarily significant to the human species, in terms that the animal species with the largest brain size would be and was heavily impacted by the innovative origin of cross-hemispheric consciousness.
The resultant intense traffic flow, not found to the same degree in our cousin animals, left humans ill-equipped to process the new-fangled information load, particularly as it applied to thought and imagination. For the first time ever, humans could talk to themselves, without another human nearby. In addition to thinking to ourselves our thoughts were talked out loud that elevated our communication skills with each other.
The cognitive function when hominins had different brains before the evolutionary innovation evolved the “bundle tract in the brain,” is unknown. Indeed, the advent of spoken, more exacting language, versus guttural and gestural communication, suggests a “range between two million and 50,000 years ago.”
So while the advent of human language and two communicative-hemispheres may not have evolved at exactly the same time, the effect of combining the functions of brain physiology and speech organs indicate the evolutionary platform from which hominins evolved was the real beginning of human culture. And, with it, came all of the good and bad characteristics that the top mammalian thinkers brought to this planet.
Nevertheless, the question of who, what and where there exists consciousness cannot be answered outside of our mammal brain functioning.
Until we have proven methods to measure consciousness in any other state of existence, it means, in a very real sense, it’s all in your mind.