Darwin's misunderstood perspectives:

 
   
Martin Johnson Heade (1819-1904)
                                                                                                                          Blue Crested Hummingbirds
                                                                                                                          circa 1864
                                                                                                                          Oil on Canvas
                                                                                                                          12 x 10 inches


 

Tree of life

                                                                                                                       

pp. 73 - 157. Who says?

What evolves?  |  Three TheoriesConclusions | Opponents


Opposition to the Darwinian ideas such as laws of variation, common descent, & gradual evolution arose from:
literalism, contradicts God's revealed truth in Genesis.
finalism, Darwin's "variations" violate the underlying, and relentlessly pursued, progression toward perfection of form and function.
essentialism, eviscerates the need for or removes the necessity of describing nature as originating from essences and forming types.


pp. 73 - 82.

Next

What evolves?  |  Three TheoriesConclusionsreturn to start
trees

What exactly is developing?

Three divergent explanations:

Typological thought: essences are all there are. From Pythagorean, Plato and Aquinas, the existence of a "natural kind."
Population thinking: groups of similar (behavioral or apparent) objects are all there are. "foundation of modern ... biology"
Finalism: teleos, said Aristotle is a belief in the end purpose of all things. Called teleology, or the study of final causes, this is the belief that "ends" are all there is. The propensity of life to move to perfection, "elan vital".

Ibid.

Next
What evolves?  |  Three TheoriesConclusionsreturn to start
trees

What evolves? "Changing in a distinctly" clearly
"directional sequence" "It is the population. And the population turns out to be the most important site of evolution. Evolution is best understood as the genetic turnover (genotype) of the individuals of every population from generation to generation."

p. 76
"the community of potentially interbreeding individuals of a species at a given locality."

(key here is access and not just desire, opportunity and fortune) even Darwin was inconsistent in its application."

p. 77
"Everybody else tended to think in terms of types."

Ibid.


What evolves?  |  Three TheoriesConclusionsreturn to start


Three theories of Evolution


 
type of belief in change:Evidence for Verdict
1) Transmutation,consistent with naturalist's observations. simultaneous mutations would be necessary.
2) Transformation, ApaptednessGeological uniformitarianism confirmed. inheritance of acquired characteristics is impossible.
3) Orthogenesis,propensity of complexity to be viewed as similar to perfection. Natural selection is a simpler and sufficient explanation.
4) variational evolutionA. R. Wallace's line in Indonesia "Population thinking" is fundamental

line
"Variation played no role in transmutationism nor in either of the two forms of transformation. 'Evolution' takes place in transmutationism through the origin of a new essence and in the transformationist theories through a gradual change of the essence."

p. 83.

"Darwin showed that one simply could not understand evolution as long as one accepted essentialism."

Ibid.

What evolves?  |  Three TheoriesConclusionsreturn to start


Ernst Mayr. What Evolution Is. Chapter 4: How and why does evolution take place?

There is a native instability in either asexual or sexual reproduction in that genes have off and on switches, crossover of chromosomes occurs, genes jump from one loci on the chromosome to another, and in small sample sizes (founder effect) the variability subject to inheritance by offspring is not ever stable but even more exaggerated than it is in larger populations.

Instability appears to be an inherent characteristic of the genotype and particularly in the expression (phenotype) of genes. Thus both intrinsic, genotypic changes and apparent, phenotypic changes are part of life's endowment.


What evolves?  |  Three Theoriesreturn to start



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