Friday, March 31, 2017

Cornelius Hunter on Evolution

"Being an evolutionist means there is no bad news. If new species appear abruptly in the fossil record, that just means evolution operates in spurts. If species then persist for eons with little modification, that just means evolution takes long breaks. If clever mechanisms are discovered in biology, that just means evolution is smarter than we imagined. If strikingly similar designs are found in distant species, that just means evolution repeats itself. If significant differences are found in allied species, that just means evolution sometimes introduces new designs rapidly. If no likely mechanism can be found for the large-scale change evolution requires, that just means evolution is mysterious. If adaptation responds to environmental signals, that just means evolution has more foresight than was thought. If major predictions of evolution are found to be false, that just means evolution is more complex than we thought."

You can find Hunter's entire piece here.

2 comments:

GalileoUnchained said...

"If species then persist for eons with little modification, that just means evolution takes long breaks."

No, if a species persists for a long time (crocodiles, maybe? coelocanth?), that means that the environment didn't change much during that time. Evolution is adaptation to the environment. If you're already well adapted, there's little need to change.

Chris Falter said...

I believe that Dr. Hunter is not depicting the scientific process correctly. To understand why, let's first look at a theory that's less controversial on this blog than evolution: atomic theory.

Atomic theory has seen numerous changes since the days of Dalton. As chemists and physicists have made discoveries, the details and mechanisms that underlie atomic theory have shifted, shifted again, and shifted even more. The plum pudding model emerged, then gave way to the planetary model after Rutherford's experiments. But the planetary model had problems explaining electromagnetic radiation (EMR). Building on experimental evidence of discrete energy levels in EMR, Bohr propounded a new theory: a quantum theory of electron orbits called, appropriately enough, the Bohr model. However, it couldn't explain emission lines of elements other than hydrogen. This required an understanding of isotopes, which emerged from Thomson's experiments.

Are you catching all this? Atomic theory kept changing not because being an atomic physicist means there is no bad news, but because an understanding of complex phenomena can only emerge very gradually, with fits and starts, under the persistent probing of science.

I haven't even touched on the developments of more recent decades, such as Bell's Theorem, "many worlds" quantum theory, quantum field dynamics, quarks, the Higgs boson....Each new development has refuted many competing models within the general category of atomic theory. Yet we do not say of the field, "those physicists and chemists just cannot get their act together. Look at how many wrong predictions so many have made about the evidence over the past decades! Look at how many models have been discarded!"

Instead, we should say:

"Within the general category of atomic theory, many models of mechanisms have been proven wrong. Yet we do not for that reason regard atomic theory as wrong. Indeed, over the years, the support for atomic theory has only gotten stronger as the evidence has grown broader and our understanding has been refined."

You could substitute evolutionary theory for atomic theory in that last statement and have a good understanding of the past 150 years of research in biology. A lot of models about biological mechanisms have been refuted by evidence, as Hunter notes. This is to be expected: biology involves incredibly complex (and wonderful) phenomena. At the same time, the models (such as neutral theory) that that have prevailed are much more solid and reliable. About the theory of evolution, we should say:

"Within the general category of evolutionary theory, many models of specific mechanisms have been proven wrong. Yet we do not for that reason regard evolutionary theory as wrong. Indeed, over the years, the evidence for common descent due to selection acting on variation has only gotten stronger as the evidence has grown broader and our understanding has been refined."

Readers should also be aware that many Christian biologists do not agree with Hunter's handling of mathematical modeling, nor with his description of notable biology papers. If you are interested in exploring Hunter's discussion with these Christian biologists, check out Biologos forum threads here and here.

In Christ,
Chris Falter