Explaining natural wonders (Animals)

by David Turell @, Saturday, March 26, 2016, 14:37 (1180 days ago) @ dhw

DAVID: You are correct in that the word 'saltation' is agreed upon, but my interpretation of saltation is different than yours. For me saltation is the arrival of a fully functional organism/ species with no need for natural selection to act. In Darwin-speak NS acts upon variations and chooses/judges which is best. Vast difference.

dhw: I'm not sure what you mean by “the arrival”. I would define a saltation as a sudden major change from one generation of an organism to the next. (Please give me your definition if different.) There may well be times when it is difficult to distinguish between a saltation and a variation, but if you believe in common descent, every saltation - just like every variation - must take place in an existing, functioning organism.

I think you are correct and I will alter my statement above. Saltation is a major change in an existing species, a disconnect from the past, never a simple variation. It may occur in the same species, or be so different, it is the creation of a new species. Punctuated equilibrium was an attempt to theorize about this. Gould made a major point of all the 'jumps' in the evolutionary bush. It is a term for sudden speciation but does not explain it.

dhw: I hadn't realized that Darwin's commitment to gradualism was already under fire, even from his close friend Huxley!

Doesn't surprise me. Darwin was not instantly accepted as he is today.

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