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In honor of Darwin Day Feb. 12, 91����Ƶ Boulder evolutionary biologist Daniel Medeiros explains what we get right and wrong about Darwinism

For evolutionary biologists, the big day is imminent.

No, not Valentine’s Day.

For many scientists, educators, historians and humanists, the upcoming event of note is��, which supporters say is a time to reflect and act on the principles of intellectual bravery, perpetual curiosity, scientific thinking and a hunger for truth, as embodied by .

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Daniel Medeiros, a 91����Ƶ Boulder professor of ecology and evolutionary biology, notes that while Charles Darwin didn't originate the idea of evolution, "I think he did the best, most comprehensive way of presenting things."

The noted British naturalist and biologist is widely recognized for his book,�� which is considered the foundation of modern evolutionary biology. Darwin Day is celebrated internationally every Feb. 12, the anniversary of Darwin’s birth on Feb. 12, 1809, outside of London.

Scientists say it’s hard to quantify the impact Darwin had on evolutionary theory. At the same time,��, and some propagandists have used his scientific theories to support a variety of�� and, in some cases, would likely be appalled by.

Recently, Professor��Daniel��Medeiros with the 91����Ƶ Boulder��Department of Ecology and Evolutionary Biology talked with Colorado Arts and Sciences Magazine about some of the mistaken ideas associated with Darwin while also delineating why some of his scientific concepts can be so difficult to grasp. His responses have been lightly edited for style and condensed for space.

Question: One idea about Darwin is that he originated the idea of evolution. True or false?

Medeiros:��False. I actually had a colleague, Ned Friedman, a plant evolutionary biologist, who taught a whole course on evolutionary thinking before Darwin. And in fact, Darwin’s own grandfather, Erasmus Darwin, had some pretty clear evolutionary thoughts and logic. I think Darwin collected the most data and articulated the best case for evolution by natural selection, but he didn’t come up with it out of whole cloth.

That’s how things happen in evolution—there’s ‘convergence.’ Similar solutions can occur in different lineages around the same time or given the same environmental pressures. That’s the idea of evolution by natural selection; I think several scientists came to that conclusion simultaneously. So, it wasn’t all Darwin, but I think he did the best, most comprehensive way of presenting things.

Question: What about the idea that Darwin’s theory on evolution encompasses the origins of life?

Medeiros:��I think he may have hypothesized on the origin of the living creature from a primordial soup of chemicals, but I don’t think he knew enough about chemistry or cell biology to go beyond that. I don’t know how he would have even begun to hypothesize about cellular evolution.

Question: What about the idea that Darwin believed humans are descended from apes?

Medeiros: ��That’s kind of a tough one, even for some of my students in my upper division class. The proper way to think about evolution is as a family tree. The idea that humans evolved from a chimp or humans evolved from a monkey; specifically, what you think of a modern monkey, is incorrect. It’s easy to conceive given that those modern species are clearly related to us, but we are not descended from them.

Now, our last common ancestor looked something like a chimp and would definitely be classified as a “great ape”. We also had an ancestor who looked something like a monkey, but technically, ‘we came from a monkey’ is not how you would describe it in evolutionary biology terms. We evolved from species that were chimp-like, but we’re not chimps and we did not come from modern monkeys.

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During his visit to the Galapagos Islands, Charles Darwin observed that different finch species had varying beak lengths, which supported his theory that species evolve to exploit their food sources and habitats. (Illustration: from Journal of Researches by Charles Darwin)

Any species that’s alive today is a successful modern species, as much as we are. If it’s around today, it’s a survivor. It’s a successful species that has its own set of innovations. If it’s living today, it’s its own success story.

Question: What about the idea some attribute to Darwinism that modern humans aren’t evolving?

Medeiros:��That’s incorrect. That’s a property of all living things—that they are always changing. It’s not something you can stop. DNA is always accumulating mutations. There’s always genetic variation, and that variation responds to the environment. In the short window of time we have been around, it’s hard to see, but it’s true.

I’m not sure how we’re evolving, but there’s no organism that’s not evolving. So, we’re changing for sure, in some way, but I don’t know how. It will be interesting to see.

Question: There’s also this idea associated with Darwinism that animals are deliberately attempting to adapt to their environments. Accurate or not?

Medeiros:��That’s a misconception. The word ‘evolution’ means unfolding, originally, which implies that you have some truth or something that’s��unfolded or revealed. But it’s actually much more chaotic and there’s a huge random factor.

From the organism’s perspective, they’re just throwing out babies with variations. And hopefully, one of them sticks. And��if one sticks, your lineage��hangs around and has another chance for more mutation. So, it’s��random and it’s chaotic.

Andthere are limitations. Species go extinct all the time. Maybe their environment changed too quickly, and they were unable to adapt. Maybe they just didn’t hit upon the right��mutations, or there could be constraints to their��development or their genome that wouldn’t allow adaptive��traits to evolve and they go extinct. That’s common.

(The word) ‘evolved,’ in terms of how people use it in common language, it’s like, ‘Oh, I evolved. I became better.’ It’s about this idea of better��and more. But then extinction is evolution, too. It’s just change over time,��however, that manifests itself.

A cool thing that I teach in my class is that a lot of animal evolution since the Cambrian or a little later—has been about loss; trimming down, getting rid of what you don’t need. I think that’s one thing that’s not really recognized too much, that evolution is not always—or even mostly—about gaining fancy new features. It’s not necessarily this march toward more and more sophistication. It’s a lot about use it or lose it—about losing features that are not adaptive anymore. A lot of evolutionary change, especially in animals, is loss.

Then you have these blockbuster new things, like feathers, which are a huge innovation, or a turtle shell, or the human brain, which is another huge innovation. But then, even more than that, what makes a lot of species different from each other is that they’ve lost different things.

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Charles Darwin, seen here in an 1881 portrait, published his theory of evolution in his 1859 treatise On the Origin of Species. (Photo: Hulton Archive/Getty Images)

Question: Why do you think it seems so hard for people to grasp the idea of evolution?

Medeiros:��Evolution is hard to understand because it’s inherently about processes beyond any individual’s experience. It’s about things happening on a scale of tens, hundreds, thousands and millions of years. That’s hard for us to fathom, and it’s not necessarily intuitive.

It’s kind of like the idea of the earth spinning around the sun. That’s not intuitive. If you look outside, that’s not what you see happening. You don’t feel like you’re spinning. The sun moves up over you. It defies your experience as a human.

So, it’s easy to have misconceptions and I don’t fault people for that. It’s a hard, hard concept just by itself, much less the implications where it could be perceived as taking human beings down several notches, as just another animal that evolved.

Question: There is an idea in some quarters that evolution and religion, whether it's Christianity or another faith, are incompatible. Any thoughts on the notion that if you believe in one of those ideas you can’t believe in the other?

Medeiros:��I think that’s mostly on the religion side of things. It’s really up to you, whether you, as a religious person, can believe in evolution. That’s a great thing about religion: If you want to incorporate evolution into it, you could surely work it in, but if it somehow interferes with your beliefs, you won’t. You can shape your religion to exclude any kind of science, if you want.

In my education, I’ve had several biology teachers, evolutionary biologists and otherwise, who were quite religious people and (evolution) didn’t interfere with their belief.

As I understand it, Darwin himself was a religious person for most of his life, and finally ended up calling himself agnostic. You can see some of that in his writing. With some (discoveries) it was like, ‘OK, where does this place God? This evidence maybe puts the role of God in a different place than I was taught when I was younger.’ I think he used some language like that in his writing.

I’m not a historian, but I don’t think Darwin ever excluded a role for religion.

Question: It seems like not long after Darwin published��The Origin of Species, people began using his work to promote their own political, religious or ideological agendas?

Medeiros:��Yes, 100%. I couldn’t give you the exact timing on when that started to happen, but I think it was while he was still alive that people began to formulate ideas around his work. I think that’s not uncommon: You figure out some scientific truth and there will be people to exploit it for good and bad.

Evolution by natural selection and survival of the fittest—all of those touch phrases and concepts—in isolation have been used to justify some very horrible things.

Question: The Darwin Awards were created a few years back as a tongue-in-cheek honor bestowed on people who removed themselves from the gene pool by doing something really dumb. How far removed are those awards from anything associated with the actual British biologist?

Medeiros:��I remember first hearing about them in graduate school. At the time, I thought it was humorous, but after I became a parent, the idea of people getting hurt and dying in weird ways was no longer so funny.

And really, that’s not how natural selection works. It’s not like, you’re an evolutionary loser, so you get attacked by a lion because you’re dim-witted.

Really, it’s all about the numbers at the margins. For example, with this particular��adaptive allele, you have lineage that has 5% more offspring—and you do that over many generations and throw in some random environmental change—and they’re the fittest. But their fitness is just kind of at the margins and there’s a lot of luck involved, too.

So, it’s not as clear as, ‘Oh, this is person’s a ding-dong; they strapped themselves to a rocket' or whatever. That’s not an accurate representation of Darwin’s ideas.

Question: Will you be doing anything for Darwin Day this year?

Medeiros:��In past years I’ve given a talk about Darwin, mentioning some things about the ‘modern synthesis’ concept, which includes things that Darwin was not aware of at the time—filling in some of the gaps he was unaware of—like DNA and genes.

That’s not to take anything away from Darwin. It’s fun to read Darwin because he’s so modern in how he thought and deduced things. I think a lot of biologists feel like, ‘Well, if I was back then, that’s how I would have figured things out, too.’

But to answer your question, nothing special planned, like reading from Origins. I might celebrate by going to my lab and writing a grant.�� Also, my youngest son has the same birthday as Darwin, so we will be focusing on that! I think Darwin would appreciate that … by all accounts he wasn’t just a great scientist, but a really devoted dad.

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