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Evolution
(written 2007; revised 8/2013)

9/2007: the discussion below focuses on evolution as a principle. Perhaps more important, or at least easier to swallow, is a focus on science and religion and how they seem to completely agree about one thing: the importance of cooperation

Introduction
When one person or group tries to push a religious belief on another person or group, this often leads to conflict, right? Perhaps you've learned not to raise the subject while visiting your in-laws, for example. Even discussing "politics" can end up the same way, of course.  Best not to get into it, if you know from the beginning you disagree -- unless you have a solid relationship and enough time to work through some tough spots and enough respect for one another to be able to step back and agree to disagree.  

Somehow the concept of evolution leads quickly into similar conflicts.  Many religions seem to find the concept threatening, and some have mounted active campaigns to push back against the concept, and in some cases even to try to declare evolution to be "wrong".  Clearly there is something about the concept of evolution that can lead to really powerful, emotional reactions. Any discussion quickly leaves the realm of calm, rational thought.  

So I realize that saying anything about evolution on this website could easily offend someone.  I also realize that trying to discuss evolution and religion with someone who might have a different point of view is difficult under the best conditions.  Trying to do so by writing an essay is really more likely to be "venting" than doing something constructive. But despite understanding this, I vented off the short version below. Just couldn't help myself.  

  Outline

Short Version

Many people in the United States don't believe that evolution is an accurate model of how humans are related to the rest of the living things on this planet.  As a 2005 Pew Research poll discovered, 42% of Americans think that "living things have existed in their present form since the beginning of time." 


(from the website of the NY times; here's the entire article
The graphic is so good I couldn't bear to see it get lost
 when the article is removed from their site. 
I'll take it down if anyone objects to this use.)

Maybe you think Psychiatry is somehow an offshoot of the Devil's work.  That's not entirely unusual.  But if you're not one of those folks; if you think that Psychiatry might be an emerging brain science that actually has something to offer (for the best demonstration of that on this website, see the current research on the brain chemistry of depression); then you'd perhaps be interested to know that every research article I've ever seen in medicine, every single one that ever mentions the idea of evolution, does so without any hesitation whatsoever as to whether evolution is an accurate model of how change has occurred over time.  In other words, every brain scientist, every molecular scientist, heck every cardiac researcher for that matter -- they all simply assume that natural selection and evolution over time are the way things actually work.  They're not running into problems with the theory. Their research consistently makes evolution seem the most sensible way of explaining things (like why the eye is built backwards; or why we have gill structures during our fetal development; or why we can go genetic research on other primates and easily extend those results -- accurately -- to humans). 

Remember, it's one thing to shoot down someone else's explanation. It's another matter to propose an explanation that works better. Until you have a better model, one that explains what we can all observe and agree upon better than evolution does, then you can't make evolution "untrue" just by pointing out aspects of life that don't appear to fit within evolutionary principles. You have to have a better explanation. You can invoke "God" if you want but then we aren't talking about science anymore. As long as we're talking about science (such as about brain changes that are related to mood and anxiety problems that make people want to be dead, or unable to function in society), then we should stick with science-style explanations of things. Yes, I know, many would invoke God to solve people's problems, and often they would succeed that way. I have no problem with that. Success is good. But if you want to know how those successes come about, especially so you can make them happen more frequently, and faster, even for people who don't believe in God, then science seems to be doing better at that, overall. Psychology, a social science, led to a treatment for panic disorder that has an 80% success rate (better than medication), and also to the experimental system which showed that the long-term success rate of this therapy is better than medications.

Granted, the concept of God is more important than the concepts of science, in several ways, in our current society. But these are separate ways of thinking. We don't expect that our prayers are accurate predictions, much as we might wish for them.  By contrast, in science we measure the accuracy of an explanation by how well it predicts the outcome of experiments, or what we'll find when we go look somewhere we've not been before (such as inside brain cells), or how to make sense of things like fossil brains or the remarkable similarities across different animals' brains

Evolution is one of the best-working explanations in science. People may try to convince you "it's just a theory".  Make them show you a better explanation for things such as finding the bones of a creature that looks like a whale but has tiny little legs in the Egyptian desert -- just where the evolutionary model said you should go look for a whale ancestor, based on the shallow seas known to have been present there around the time those ancestors should have been swimming around.  Why else did God put those bones out there? Which seems like simpler explanation, at this point: that God works in all sorts of strange ways, even putting bones in the desert where we'd think to look for them if we got the theory right...or that the whale ancestors put them there? Sorry, got carried away there. Time to remind myself that this debate I'm dancing on the edge of is not about science, and not about rational thinking, but rather about emotion-driven thinking.  Evidence of which you might be experiencing right now?

Read any solid (not politically manipulated) biology texts. You'll see that there is virtually no debate in biology about whether evolution is the most accurate model to explain what we observe.  The remaining debates are only about how to tweak the model to make it work yet more accurately.  And there is almost no debate at all about evolution amongst us biologic scientists who are busy trying to use the information it organizes, such as the data you'll find on this site (one fellow announced himself as a creationist at a lecture at the American Psychiatric Association meeting this year, a talk on using evolutionary concepts in psychiatryNesse. There may have been other non-believers in the room of about 1000 or more, but one would not be able to tell, as there was no debate at all about the accuracy of the evolutionary model. Of course, a room full of non-believers is probably not the place to look for dissent, I grant you. That one fellow who stood up was a brave soul.)

So, that's why on this site you'll find explanations unhesitatingly refer to evolution. It's by far the best model for explaining things in this business -- as long as we're still talking science: predicting outcomes, predicting what we'll find when we look for a particular explanation. Today's example, as I write this:  why do some people with bipolar disorder respond to lithium, and some not? Is there a connection to the genetics of bipolar disorder that might shed some light on this illness? Looks like maybe so: two long versions of a serotonin-related gene that's been studied in depression predict better response to lithium.  Isn't it interesting that this gene length difference appeared only very recently in primates. Chimps have it, but primates with less complex social lives do not. Intelligent design? Get two short ones and the risk of suicide, if you have a rough childhood, goes way, way up, as shown in the essay on this finding.  But why didn't natural selection make short genes just disappear then?  Ah, now you're getting well into that story; you'll find the current explanation, a working estimate, in Chapter 4 of that same story. 

But do explanations like this change people's minds about evolution? I doubt it (write if I'm wrong about that!).  Better to start by really understanding how people who have trouble with evolution see things, and why.  That's part of the long version...

Long Version
I once had it in mind to write the following as a book, but there's a better one to read now ( Righteous Mind, by Jonathan Haidt)

These are the features of human behavior that will either save us or destroy us, wouldn't you agree? Woudn't it be wise to understand them as well as we possibly can? To bring all our best scientific understanding to this challenge -- along with our best religious minds? I think I can put this together in a book that people can swallow even if they believe strongly that the earth is 4,000 years old and that nothing like evolution every happened.  Now there's moxie for you, eh?

All right then, how did you get here? What page were you on, anyway? Go back there! 

evolution and antibiotic resistance
Okay, before you go, here are two funny things: first, a Doonesbury comic that pokes (hard) at intelligent design; and then, perhaps funnier if it weren't somewhat sad, the response to the comic strip (a sad funny statement in itself?) from the intelligent design people.  The ID people seem to be admitting that natural selection takes place just as the cartoon suggests, but they insist that because "the resistance was already there", the evolution of antibiotic resistance doesn't prove evolution. 

In fact, they say, it rather disproves it: "this is the opposite of evolution, which requires an increase in information if it were to occur."  Sorry, there is no principle in evolution that requires an increase in information. But it makes the authors sound authoritative anyway.  If I really believed in intelligent design and was looking for a way to disprove evolutionary principles, this little essay from Answers in Genesis would be an embarrassment.  They way they just accept the idea of natural selection, with no hesitation or quarrel -- wow, that's just abandoning half the battlefield right there.  Okay, let's just argue about whether mutations really occur or not, that's even easier to demonstrate! 

Two relevant articles

Oh wait, if you want to see a classic example of evolutionary reasoning applied to bipolar disorder, here are two classics. 

1. At least some of the genes for bipolar disorder evolve from adapting to life in the far North. There is an elegant paper which lays out the evidence in support of this presumption by Dr. Julia Sherman. Read the one-paragraph summary, it is fascinating.

2. . Dr. Akiskal, a well-known bipolar researcher, wrote an essay about how "temperament" -- a person's underlying emotional style, such as pessimism or optimism -- might be connected to the illnesses we call bipolar disorders. 

His article appeared in the on-line journal Medscape in 2003.  Medscape will ask you to register there, but it's free, and they have a lot of good articles. Go ahead and register, then take that link. If the link is no longer working, then here is the text of his article, which I've saved (they don't seem to save theirs).