The Truth About Evolution

I am working my way through The Evolution-Creation Struggle, by Michael Ruse, a philosopher at Florida State. That's important: he's not a biologist for whom science can do no wrong and religion can do nothing right, he's a philosopher interested in a broader set of questions about the protracted debate between science and religion. I'll cover topics from the first half of the book in this post.

The first point is that evolution didn't start with Darwin. It was in the air ever since the Enlightenment produced a a general belief in the possibility of human progress. Christians could be as progressive as more secular thinkers. The idea that human effort could and should make the world a better place was a central tenet of postmillennialism and of the social gospel of the late 19th century.

How the notion of progress was incorporated into geology and biology is a messy tale. Scientists inherited the non-evolutionary worldview bequeathed by Plato and Aristotle as well as the short timeframe depicted in Genesis. Design was evident in plants and animals, which were and are well-adapted to their various environments. Early evolutionists like Erasmus Darwin (grandfather of Charles), Jean-Baptiste Lamarck, and Robert Chambers struggled to give explanations that accounted for the growing body of evidence showing similarities between different but related species, and also to account for the fossilized remains of many now-extinct creatures, including dinosaurs whose enourmous bones were discovered about this time. It didn't help that such evolutionary speculation was often made part of the social and political disputes of the day.

So by the time Charles Darwin was becoming a young naturalist, key work in related fields (Malthus in economics and demography; Lyell in geology) was just emerging. In 1831, Darwin rather boldly set out on a five-year mission to explore the flora and fauna of a new continent by signing on with the captain of HMS Beagle. Darwin did fine fieldwork, and his careful reflections on what he saw and collected changed his life. It changed everyone's life. Darwin also happened to be a good writer (he picked up rhetoric somewhere in his earlier education for the ministry), so when he finally got around to publishing The Origin of Species in 1859, it did what no earlier work on evolution had done: it made a sound and defensible scientific case for evolution.

But Darwin's theory was not widely accepted. The evidence for and discussion about evolution was not the problem for many readers, both secular and Christian. The problem was that almost no one agreed that natural selection, Darwin's mechanism, was sufficient to produce the sort of changes that a theory of evolution was supposed to explain. Geologists and physicists of that day put the age of the earth at a hundred million years, not sufficient time for the accumulated incremental changes posited by Darwin to accomplish the work of evolution. Other scientists proposed other mechanisms that were more widely accepted at the time. Darwin had no good candidate for a mechanism of inheritance (genetics did not emerge until the 20th century). When Darwin died in 1882, it was not at all clear that natural selection would end up being the primary driver of evolutionary change or that Darwin would attain the enduring scientific stature he has today.

But the best known evolutionist of the 19th century wasn't Darwin, it was Herbert Spencer. Where Darwin was always reluctant to make racial, social, or political pronouncements based on evolution or natural selection, Spencer and a host of others were quite happy to do so, although they rarely got the scientific details right. Social Darwinism, laissez faire economics, feminism -- the range of topics one could evolutionize was almost limitless. Eugenics, unbridled competition in industry, and militarization also made the list of popularized evolutionary applications. By the dawn of the 20th century, it was evident to many that progress, the social application of evolution, had a dark side ... and that was before World War I, genocide, and totalitarianism. The story of evolution in the 19th century did not end on a high note.

Upcoming topics: Christian responses to evolution; how science reclaimed evolution and natural selection; is evolution a secular religion?

Comments

[Dan]

It's fascinating just how powerful even the smallest ideas are. Go from the discovery of natural selection to the attempt at controlling selection with eugenics. Frankly, I say keep revealing the truths of this world and of life.

[djinn]

Herbert Spencer was not a Darwinian evolutionist. Which isn't even close to the modern synthesis that is understood today. For fill in the lord's sake, the guy was at least partially a Lamarckian. Darwin explicitly denounced social darwinism. The name is a misconception and flat-out wrong. Evolutionary theory posits that some critters leave more living offspring. Mis-named "Social Darwinism" is all about human class standing. More money equals more value. It's just prejudice pretending to be sciency, but failing.

[Joe]

A lot of things can and do become a secular religion: politics, the military, guns, economic growth, to name a few. Forty-seven incoming Republican members of congress do not believe man has had any role in global warming. I hope you will explain where you are going with this because Darwin lived a century and a half ago. The world has had plenty of time to take his ideas apart since that time. When you ask if evolution has become a secular religion, it sounds as if you are dismissing it in a rather cheap fashion.

[djinn]

Evolution is a fact (as evidenced by the fossil record, living organisms and DNA) and a theory. Calling it secular religion is redefining the word "religion" so as to make it meaningless. Is geology a religion? Biology? Genetics?

[Dave]

Thanks for the comments, everyone. It sounds like the secular religion post will lead to a spirited discussion.

[Dave C.]

2 facts about evolution:
1. Microevolution is a proven fact.
2. Macroevolution is not at proven fact, but is supported by factual observations, which is why so many believe in it.

For a more detailed explanation of these two points from a philosophy of science perspective, see http://www.mormonsandscience.com/1/post/2010/10/methodological-smackdown-darwins-tiktaalik-vs-einsteins-1919-solar-eclipse.html

[Dave]

Thanks for the link, Dave C. I visit your blog regularly, of course.

I'm not fond of the micro- versus macroevolution distinction. That is terminology that comes from conservative Christians who reject evolution, not from the science. The presently accepted science describes one natural process (natural selection) that drives evolutionary change over time. The rate of change is responsive to environmental pressure, of course -- rapid climate change or a catastrophic meteorite strike, for example. But there is just one process.

I am sure some of this is covered in later chapters of the book -- I'm not quite finished yet. More posts to follow.

[rob osborn]

I disagree that natural selection is the driving force in the theory of evolutionary change. This makes it seem that changes needed in a an environment are preselected or guided in some way in which i disagree. Darwinian evolution theory is about selection derived after copy errors and/or mutations in the DNA structure change it to something else. So in reality the mechanism that drives evolution in Darwins theory is a complete random event.

In this theory it is only after a DNA structure is canged that it is selected or dropped. The mere selection process however does not drive the process that brings about a greater change in a species.

Also confusing here is that genetics play a role in the Darwinian selection process but that these varriations in genetic selection may not lead to a new species. In the human population for example certain genes become more dominant in one region or climate than another. But these varriations have not led to a new species, just a greater varriation within our race to accomidate different climates and habitats.

In Darwinian evolution he supposes that these genetic varriations can add up over time to a new species. But this has not proven out and so they couple this with the main mechanism- that of copy errors and mutations.

Therefore, the main cause or drive in Darwinian evolution is random copy errors and mutations. Selection of these copy errors or mutations has not really been identified as leading to a new species let alone being the driving force in evolution.

This is simply a case of putting the cart before the horse.

[Dave]

Thanks for the comments, Rob. It is true that essentially random but small changes in DNA makeup create the variation in the gene pool that gives natural selection something to work on -- if a population were composed of clones, there wouldn't be anything to select. Of course, Darwin did not know about DNA or genes.

I think biologists would disagree that natural selection is a guided process.