Michael Denton’s new book is out, Evolution: Still A Theory In Crisis.
Denton’s stance is for structuralism and against functionalism, especially as functionalism appears in it’s current form as the modern synthesis or neo-Darwinism (the cumulative selection of small adaptive changes).
Denton argues for the reality of the types, that “there are unique taxon-defining novelties not led up to gradually from some antecedent form” and that the lack of intermediates undermines the Darwinian account of evolution. He also argues that a great deal of organic order appears to be non-adaptive, including “a great number of the taxa-defining Bauplans,” and that this also undermines the Darwinian account of evolution. Evo-devo is also showing us that “Darwinian selection is not the only or even the main factor that determined the shape and main branches of the great tree of life.”
These arguments are first set forth in Chapters 3 through 5 of the book and then defended throughout the subsequent chapters.
Denton provides a list of some of the Type-Defining Homologs:
The Pentadactyl Limb
The Insect Body Plan
The Amniotic Membrane
It is not just the major taxa which are characterized by unique defining homologs or novelties:
Even individual species are often defined by unique novelties (autapomorphies in cladist terminology).
To head off a lot of irrelevant objections and nonsense from people who can’t be bothered to read the book, Denton accepts common descent and doesn’t appeal to “goddidit” as a better explanation.
- If types exist, what does that mean for Darwinian evolution?
- Does the existence of non-adaptive order undermine Darwinism?
- Does anyone think neo-Darwinism is even relevant to modern evolutionary theory?