On the Origins of New Forms of Life: A New Theory by Eugene M. McCarthy. How does evolution occur? — That is, what natural processes bring new types of organisms into being? Expressed more technically, one might ask, what are the genetic processes that have produced the various forms scientists recognize and assign scientific names? This is the question considered in this book, and it attracted me a lot, evolution being my pet topic.
First chapter of the book opens with a discussion of the word species, a word that lies at the center of modern biological thought, examining its history, meaning, and usage. And questions the style we have acquired of attributing unique properties to groups denoted by this word. After a brief discussion about other theories is in this regard in the next couple of chapters, what is known about stabilization process and its prevalence is discussed. The evidence of the fossil record as it bears on the relative prevalence of the processes postulated by neo-Darwinian theory and by stabilization theory comes next, followed by examination of stabilization theory in detail. A rather rich background about the historical connection provide intellectual context for the discussion. How stabilization theory can be applied while re-evaluating the origin of mammals, in the light of the reasoning stipulated in this new perspective.
It then explains the stabilization theory in detail, the main tenets of which are, 1) Typical form of life treated as a species comes into being via certain processes ("stabilization processes") that produce new stable forms in an extremely rapid manner, as against the 'Typical new form comes into being gradually through the accumulation of certain characteristic traits within an evolving population over time' of Darwin, and 2) These processes produce new forms that are, for genetic reasons, inherently stable from the time of their inception right up to the time of their extinction, with negigible tendency to change over time in response to environmental constraints, as against the 'The accumulation and spread of these traits is due to environmental influences favoring the survival and reproduction of individuals having such traits (natural selection), of Darwin. In short, stabilization theory suggests we should seek to explain the origin of any given set of similar forms in terms of their derivation from some preexisting set of forms with similar traits.
As I mentioned, this being my pet topic I went into it with interest. Of course the author puts life as something produced rapidly by a stabilization process, and has a distinctive and characteristic set of traits from the time of its inception that does not change significantly thereafter. But the book does not produce a good reason that can act as an incentive to this process, though it mentions of the lack of such incentives in the explanation and analysis of Darwin's theory of evolution. I also feel, more than the modalities of the process evolution, in which this theory does not show much deviation from the classic one, one needs to enquire into the causes of evolution.
(I think, my theory of the unsure male can fit in here.)
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