Darwin, in writing his ORIGIN OF THE SPECIES, worried a great deal about why the intermediate steps between primitive and developed species, couldn’t be found somewhere in this large world. That big creature must either be an elk or a deer, nothing between.
While the vast age of the earth was emerging in Darwin’s time, it was still in transition between Bishop Usher’s 4004 BC and the current 13.7 BILLION years, now accepted by Cosmologists. (It was still “up for grabs”).
The essence of the ORIGIN OF THE SPECIES is that in this vast world conditions vary continuously from place to place, AND from time to time. (If heredity was absolutely fixed by the genetics of parents, we would still all be jellyfish!) So, we are fortunate that mutations and selection work together to make some variation possible within a species, while preserving general useful characteristics that define the species.
Hence, the Discontinuity of the Species.
This is a slow method of developing improved species, and its not surprising that it has taken 4By to evolve a rational species that can write a comment like this.
(I looked up “Discontinuity of the Species” on WWW. I found relevant articles, but didn’t find anything as clear as this.)
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