Evolution: hybridization is relatively common (Introduction)

by David Turell , Sunday, August 27, 2017, 20:01 (2644 days ago) @ dhw

QUOTE: "Other types of organisms, from fish and birds to wolves and sheep, experience their share of introgression, too. “The boundaries between species are now known to be less rigid than previously thought,” said Peter Grant, an evolutionary biologist at Princeton University who, along with his fellow Princeton biologist (and wife) Rosemary Grant, has been studying the evolution of Galápagos finches for decades. “Phylogenetic reconstructions depict treelike patterns as if there is a clear barrier between species that arises instantaneously and is never breached. This may be misleading.” (David's bold)

dhw: The problem of what is meant by “species” is not exactly new. “Nor shall I here discuss the various definitions which have been given of the term of the term species. No one definition has as yet satisfied all naturalists. […] The term ‘variety’ is almost equally difficult to define.” (Charles Darwin, Origin of Species, beginning of Chapter 2).

DAVID’s comment: Hybridization is an area of research that must be pursued to gain more understanding of its role. It points out how little we understand about initial speciation and its causes. Why should there be five 'big cats', all closely related? Why does evolution do that? I'm musing without the possibility of God's role in creating new species. One obvious causality.

dhw: If you want to muse about a possible God’s possible role, perhaps you might ask why he should have preprogrammed or dabbled five big cats as a “necessary side purpose”, if his sole purpose was to produce the human brain.

Bush of life with eco-niches, of course. As for Darwin this Times essay is very damning about Darwin's scientific and intuative abilities:

https://www.thetimes.co.uk/article/darwin-s-greatness-is-founded-on-a-myth-r0563g83q?sh...

I won't bother to quote from the essay. You can read it for yourself if you can tolerate the point of view expressed.