Haldane 1937
From Genetics Wiki
Citation
Haldane, J. B. S. (1937). The effect of variation of fitness. The American Naturalist, 71(735), 337-349.
Links
https://www.journals.uchicago.edu/doi/abs/10.1086/280722
https://www.jstor.org/stable/2457289
Notes
Paragraph One
Haldane points out the distinction between Darwinian evolution (novel adaptation) and stabilizing selection (or purifying selection or "maintenance" selection).
Paragraph Two
The change in frequency of alleles resulting in novel adaptation can be very slow in terms of a human lifetime; however, extremely fast on a geologic timescale. Very small fitness differences in numbers of offspring could be virtually impossible to detect by direct observation yet have a very real evolutionary effect.
Terms
Facies - appearance. https://en.wiktionary.org/wiki/facies