A Circle in a Square

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R.M. Brockman


Charles Darwin’s theory of evolution was founded on the core belief that natural history is one of slow, incremental change, a concept he called ‘speciation’. A hundred years later Eldredge and Gould challenged Darwin’s theory arguing that the data of paleontology reveals something quite different: long periods of stasis followed by bursts of change, a concept they called ‘punctuated equilibria’. This paper will follow that progression and then describe the three ‘punctuated equilibria’ that I believe led to homo sapiens. It argues that two of the three transitions are revealed in the hard data of the fossil record. The third is in the soft tissue of the brain. The third punctuated equilibrium placed homo sapiens outside of evolution. Its arrival 50,000 years ago, closed the circular nature of evolution and foretells its end.

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How to Cite
Brockman, R. (2023). A Circle in a Square. Human Evolution , 38(3-4), 139-160. https://doi.org/10.14673/HE2023341117
Author Biography

R.M. Brockman

Brockman R.M., MD 
Clinical Professor, 
Department of Psychiatry,
Columbia University,
Vagelos College of Physicians and Surgeons