>But almost 140 years have elapsed since Darwin's *Origin* was published. The
>scientific resources available to research the role of natural selection at
>the higher taxonomic levels are enormous. How much more time is needed?
Have you applied to the NSF for funding to study the role of natural
selection at higher taxonomic levels lately?
>I simply maintain that Darwinian natural selection is not competent to
>account for what is called macroevolution, what I prefer to call the
>formation of morphologies at the higher taxonomic levels.
This does not directly follow from the quotes about the micro/macro
controversy. In this context, microevolution includes universal common
descent through the process of natural selection. Disbelief in
macroevolution here is a belief that cummulative population-level small
genetic changes can get from bacteria to humans. Belief in macroevolution
here often means a belief that natural selection can act on species and
higher groups and not just on individuals rather than a disbelief in the
effectiveness of natural selection to account for the patterns.
Additionally, there are factors such as sexual selection, catastrophes, and
large mutations such as duplication of large parts of the genome that do
not fall under natural selection as strictly defined.
Natural selection does sort of have a long-term positive influence in that
continued selection over time tends to produce cummulative improvement,
though leveling off in some areas. For example,in studies generating a new
function for a gene in a lab organism, the first few mutations in the right
direction are generally major improvements. Afterwards, the amount of
improvement per mutation tends to drop off rapidly. Mutations of an
existing gene tend to produce very slight improvements or decreases in
efficiency, if they have any phenotypic effect.
David C.
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