I look at what we humans do every day all day long in the course of living and see biological marvels. So I have found that a summary, i.e., a brief conceptualization encapsulating a developed set of ideas and data (you know, information), is helpful (to me at least) in thinking and talking about our biological roots. I have two main ones for rendering my ideas. I posted about the genetic watersheds previously and here is the second, the soma, its brain and the MEMBRAIN. The basic idea is that the soma (the body) and its brain have evolved as the genes flowed down from the Solving World Problem watershed to our pool and so shaped our current evolutionary form. With the additional flow from the Conspecific Relations watershed that began with sexual reproduction, the brain began to develop special abilities related to mating, communication, child rearing, and group formation and maintenance. These new exaptations specifically supported social relations and eventually brain systems became dedicated to these functions, and in doing so became the MEMBRAIN of the mind. The brain thus developed a MEMBRAIN because family, tribe and group relations turns out to be a very powerful factor promoting evolutionary adaptability. (This underlines the prominent place of mammals, including us, in the evolutionary tree of life—see recent posts about Mammalian Heritage Day).
A cursory glance shows how somas have evolved through the eons of life on Gaia. Changes in sensory and perceptual capabilities along with changes in motoric abilities have yielded many varied life forms that cover the planet and its many niches. One of my favorite examples is birds migrating thousands of miles attuned to the seasons and guided by geography and the magnetic field of the earth. Another is that fish can be frozen and thawed out some time later, then brought back to life, their biological clocks picking up where life’s rhythm left off. Insects are incredibly prolific, diverse and successful. Cockroaches have maintained essentially the same form for many millions of years. Butterflies range from drab to brilliant. Oh, the list goes on to include all of the living organisms on our planet from the net of fungus and other microorganisms thriving just below the surface to humans as we leave for other worlds.
Similarly, brains have evolved to greater and greater complexity thereby enabling more powerful capabilities. The modern evolved brain still interfaces with the somatic external boundary for the ambient, i.e., the sensorium, and within the soma internally through proprioception, its autonomic systems, i.e., sympathetic and parasympathetic, and chemical systems, i.e., hormonal and neurotransmitters. The nervous system, central, peripheral, and autonomic divisions, maintains homeostasis and vitality. The central nervous system with its increasing encephalization generates contexts that are deep in purview and broad in scope. These then form the basis for complex intentions and plans that guide increasingly sophisticated behaviors. Over the course of evolution, then, brains enlarged perceptual processing and integration, memory systems, motoric control, management of impulses and implementing complex purposive behaviors. And all of this is contingent upon emotional control and stability, i.e., nervous homeostasis.
With the rising evolutionary importance of conspecific relations, extant systems in the brain were dedicated to social interaction through exaptation that led to further development of systems to form the MEMBRAIN. Recognition of individuals, coordination of mating and child rearing practices along with signal communication appeared early on. The advent of live birth, altricial young and a prolonged juvenile period increased the importance of parenting, cooperation and communication. Systems operating with empathic communication through kinesic channels developed from facial recognition and increased with social agency. Neurologically this resulted especially in enlarged parietal and temporal lobes that increased the complex interplay between occipital and frontal lobes. The momentous developments of attachment and individuation based upon a powerful empathic sense of others led to a sense of self, and then culminated in symbolic communication to share information displaced in time and space, i.e., mentally and not perceptually generated information, among each others’ minds. The MEMBRAIN, then, initiated with social interaction, became the organ controlling mental information, and finally constituted a interpersonal shared organ supporting or comprising the habitus and cultural learning, i.e., the social mind composed from many individual minds.
This summary shows the constancy of what I call the 4 membrane functions: keep material/information in and out, pass material/information in and out. Even the first soma fulfilled these four functions in order to solve the basic world problem of obtaining nutrients and eliminating wastes and keeping toxins out while keeping metabolic machinery protected within. This is all in keeping with mitigating exigencies and exploiting opportunities (chance and necessity). Early somas’ membranes evolved in more complex organisms to become skin that then fulfilled these same functions. The evolutionary appearance of brains continued these operations, and it makes perfect sense that neurological tissue develops in the embryo from the same tissue as skin. With the powerful transformation enacted by CR the MEMBRAIN appears and these specialized systems fulfill the membrane functions for social/mental information. It is all of a piece.
This synopsis of the soma-brain-MEMBRAIN evolution shows the biological roots of our humanity from deep in mammalian evolution through primates (50 million years ago) and then hominids (500,000 years ago). And that led to cultural evolution of the past 100,000 years or so, especially the most recent 15,000 years since the advent of agriculture. Time to travel on to #4: some things I have learned from doing this blog.