Vitruvian Man - The Cosmography of the Microcosm.
Leonardo Da Vinci (1452-1519) saw Nature´s pattern and proportion in the Human body - it´s anatomy reflecting the living processes of the universe and the creative potential of the material world.
Like the Alchemists seeking to understand transformations of the Spirit via the transformations of Matter, Leonardo Da Vinci sought to understand the mysteries of the world by a direct observation of Nature and it´s workings.
The human bodyplan revealed the organization of Nature in a readily manifest form that was accessible to human inquiry and understanding.
We are now coming to understand that the human bodyplan, as well as the matter and spirit it engenders, is a reflection of our primate, mammalian, tetrapod, and gnathostome ancestry - We are Vertebrates at the very core of our being.
Three and a half centuries after Leonardo Da Vinci´s musings, Charles Darwin (1809-1882) would publish his seminal work On the Origin of Species (Darwin 1859) initiating the modern age of inquiry into the fundamental nature of the bodyplan and it´s evolutionary past.
Of course, Darwin was not the first to propose a evolutionary theory of life - In the 6th century B.C. the Ionian Greek philosopher Anaximander of Miletus (ca. 611-546 B.C.E.) proposed what today would be considered to be an evolutionary scenario for the origins of the world, animals, and man.
According to Anaximander animals were formed from the primordial mud and water of the earth - The ancestors of mankind were fish-like and aquatic.
Pierre Louis Maupertuis (1698-1759), Erasmus Darwin (1731-1802), and Jean-Baptiste Lamarck (1744-1829) also foreshadowed Charles Darwin in proposing that animals and plants might be capable of evolving into new varieties and species.
Lamarck proposed one of the earliest mechanistic accounts for the adaptive modification of traits within the bodyplan, but his theory failed to account for the transmission of the traits which he postulated were acquired by use and/or disuse over the course of generations.
It was Charles Darwin and Alfred Wallace who first proposed a meaningful mechanism for evolution - Natural Selection.
But it was Darwin that presented the overwhelming amounts of empirical evidence in support of the evolutionary model that established the validity of the theory.
Indeed, much of Darwin's insight came from his observations that animal and plant breeders had been engaged in selectively encouraging the formation of new varieties since the dawn of agriculture and animal husbandry.
Darwin also understood that human behaviors are made possible, and constrained, by a bodyplan that has functional corollaries in our vertebrate siblings and cousins - and, of course, our phylogenetic ancestors.
Clearly understanding the way in which the bodyplan both constrains and facilitates the behavioral potential of an organism will be key to developing a comprehensive theory of human behavior and the human potential.
These issues relate to both ontological development over the lifetime of the individual organism and the phylogenetic history of the lineage during it's 500 million years plus years of evolutionary transformation.
The primary purpose of this project is to derive an understanding of the relationship between the vertebrate bodyplan and it's behavioral potential and how that relationship has transformed over evolutionary time in the lineage leading to humans.
To facilitate our task and give us a firm point of departure we would like to 1) understand origin and organization of the generalized, or phylotypic, vertebrate bodyplan and 2) trace how the phylotypic bodyplan has differentiated into the human bodyplan in development and over evolutionary time.
Primary focus will be centered upon the organization and evolution of vertebrate nervous and endocrine systems as well as the way functional integration is achieved across the bodyplan as a whole.
It is important to express this understanding in a manner that is consistent, coherent, and integrable with the rest of the Darwinian biological sciences.
This constraint removes us from the world of logical circuits and the programmed algorithms of cognitive psychology and places us squarely in the world of cellular interactions and the somatic selective developmental systems of modern cellular and molecular biology as well as comparative embryology, morphology, physiology, ethology, and neurology.
Our approach will be unashamedly Darwinian in nature.
Being primarily interested in the evolutionary history of the human bodyplan and it's behavioral potentials; we will be concentrating our attention on the chordate lineage leading to vertebrates, tetrapods, and mammals.
The red line of the diagram below marks the evolutionary trajectory we will be following:
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The chordate stem lineage of the Vertebrates is now believed to be within the Craniata which exhibit the general features of the vertebrate bodyplan but lack a biomineralized axial skeleton.
Each node in the evolutionary pathway marks a key evolutionary transformation of the basic vertebrate bodyplan and marks the emergence of a new or modified set of behavioral potentials.