Talking evolution

Talking evolution

Celebrating Charles Darwin's legacy with evolutionary biologist Douglas Morris
February 11, 2009
On Feb. 12, 1809, Charles Darwin was born in a damp little town in northwestern England. Fifty years later, he published The Origin of Species, with his theory of evolution, the book that completely revolutionized our understanding of the natural world. To mark his birth and the genius of his theory and its impact on science, 2009 is being celebrated worldwide as Darwin Year.

As one of Canada’s leading evolutionary biologists, Douglas Morris knows a thing or two about Darwin. He is a professor at Lakehead University in Thunder Bay, Ont., Lakehead’s Research Chair in Northern Studies and president of the Canadian Society for Ecology and Evolution, one of the country’s largest scientific associations. He studies various evolutionary scenarios in mammals and teaches evolutionary and conservation ecology. spoke to Morris about Darwin’s far-reaching influence in science.

IC: In a nutshell, what was Darwin’s theory of evolution?

DM: Darwin’s great insight really comes down to three basic tenets. First is heritable variation — whether or not an individual possesses a certain trait can be passed from generation to generation. Second is the struggle for existence — essentially, that more offspring are produced than can survive. And, finally, heritable variation influences the struggle for existence — the fact that not all individuals can replace themselves.

IC: How did his theory advance science?

DM: Through these very simple principles, Darwin was able to demonstrate things that had long puzzled scientists: What accounted for the tremendous diversity of species? What about the procession of life through time? And how can we understand the distribution of species on the planet? With a handful of simple concepts, he was able to explain these things.

IC: How has our understanding of evolution changed since Darwin published The Origin of Species?

DM: We certainly understand more now about the mechanisms underlying adaptation. Darwin had little understanding of genetics, so for much of the last century, we built the genetic theory for evolution and, to a large extent, natural selection [the passing of beneficial genes to future generations]. Much of that theory remained untested until we developed genetic techniques and DNA technologies. Even though many of his main postulates remain true, we are always advancing.

IC: Some people don’t accept Darwin’s views. Why?

DM: I think we’ve had a hard time as a society accepting evolution, not understanding evolution. In our education system, most students learn the physical sciences — chemistry, physics, maybe even geology, astronomy and geography — which all reinforce one another because they are based on physical properties. But evolution and ecology can’t be understood from those same properties. I think Darwin, in essence, developed a new science. You can know everything you want about molecular structure and subatomic particles and never gain any insight at all about adaptation or the dynamics of populations or communities.

IC: Why should evolution matter to ordinary people?

DM: We’re biological organisms shaped by evolution. We’re as much involved in the evolutionary process as any other species, and we can’t break those rules of adaptation. Any well-educated person should have a grounding in the most fundamental sciences that impinge on our actions every single day. The great hope is that we would be able to use our intelligence and understanding of evolutionary processes to help solve problems, such as the evolution of antibiotic resistance, herbicide and pesticide resistance or the effects of invasive species. 

IC: What if we don’t learn these evolutionary lessons?

DM: The risk is that humans were only able to evolve simply because of biodiversity, and without a rich biodiversity, it is questionable whether an intelligent organism could have prospered the way we have. And, unfortunately, we are eating ourselves out of our home.

IC: What do you mean?

DM: Human history is full of examples. Look at the Polynesians. They went from island to island, with biodiversity collapsing behind them. They expanded across the Pacific until they ran out of islands, and then their entire society collapsed as a result. Now the risk is that humans have managed to have the same effect on this single island we call Earth, but there’s no place left to run. The only way to avoid the collapse of ecosystems and life as we know it is through our understanding of ecology and evolutionary dynamics. We know there will be major ecological and evolutionary consequences, but we don’t know what they are going to be. We need to know that, to plan our future and avoid the calamities that have plagued us for centuries as we’ve trotted around the globe leaving our problems behind us.

IC: If you could meet Darwin today, what would you say?

DM: I think I would want to discuss the huge loss of the very biodiversity that he so eloquently described in The Origin of Species. The final sentence in his book is a poetic statement on the enchantment with biodiversity and with life. I would be interested in seeing whether there were tears in his eyes when he looked around to see what has happened.