Cristián Samper on Appreciating Evolution

Cristián Samper is an evolutionary biologist and the director of Smithsonian’s National Museum of Natural History. He spoke with senior editor Laura Helmuth about his own favorite evotourism sites, both within the museum and beyond.

Which places have given you the greatest appreciation of evolution?
I realize now I’ve been an evotourist all my life! Clearly the Galápagos is one of the places. If you’re a biologist, you have to study On the Origin of Species; it’s such a classic. In some ways, going to the Galápagos, for an evolutionary biologist, is like a pilgrimage to Mecca. Very interesting research is still being done there. The Grants, Peter and Mary, have been doing really interesting work on finches, looking at contemporary evolution.

One of the trips I took this year, to Hawaii, was another. What you’re looking at there is the progression of islands. It’s most striking on the Big Island—you can really see volcanoes in action in every sense of the word. You see stripes of old lava and new lava, and from there you can go to a six-million-year-old island and really understand the formation and erosion of islands, and look at how that led to a diversity of species.

For me, some of the sites that I saw as a young biologist, in Colombia, were also important. There’s a site in Colombia just north of Bogotá in a place called Villa de Leyva. What’s amazing there is that you see all these ammonites, a lot of ammonites, and ichthyosaurs and other marine reptiles. What was so striking to me was that this site is 7,000 feet above sea level, in the Andes Mountains—going there and seeing these incredible fossils, understanding that all this was the ocean bed and now it’s way up in the mountains. It’s not a legendary site, but it was one of the places that really opened my eyes and posed a lot of questions for me as a young biologist.

What evotourism site would you like to visit?
I haven’t been to the Burgess Shale yet. It’s such an iconic collection, and so intimately tied to the Smithsonian Institution in so many ways. It’s so fundamentally important for understanding evolution and life on earth.

What is your favorite representation of evolution in the National Museum of Natural History?
I think the Hall of Human Origins is probably the most comprehensive and up-to-date treatment that we’ve done of evolution.

But we have so much work on evolution throughout the museum. For the museum’s centennial, we established the Evolution Trail, which leads through various parts of the museum, linking the whole concept in an attempt to bring everything together. There’s evolution throughout the museum. You could almost call it the Evolution Museum.

The Mammal Hall also presents a lot in terms of adaptations; there is a big evolutionary message there. And the Ocean Hall, especially the “journey through time” gallery. Even the butterfly pavilion has some interesting information about co-evolution between insects and plants. Evolution is a common theme throughout the museum.

But if I had to pick one gallery or place, it would probably be the Hall of Human Origins. It not only showcases the evidence of change, but it talks about environmental change and about adaptation.

Part of what I like about it is that it makes evolution personal. So often it’s sort of out there and distant, like the fossils from the Burgess Shale or extinct dinosaurs. But this hall brings evolution into personal contact; it shows where we come from.

One of the things I love is seeing my kids’ reaction to the Hall of Human Origins. We have a 5-year-old daughter, and that may be her favorite hall in the whole museum. She loves it. She’s been through it so many times that she can give a pretty good guided tour. She’ll walk through it and talk about the Turkana Boy and how it had an abscess and that’s why she has to brush her teeth.

What are some of the biggest misconceptions about evolution?
One of the things we always deal with is the issue of evolution and creationism. When we were preparing the Hall of Human Origins, we spent a lot of time thinking about that and understanding it, and one of the pleasant surprises we learned was that the major faiths actually don’t have any problem or issue with evolution itself.

Another misconception is that it’s a question of whether or not you believe in evolution. Evolution is happening. The evidence is absolutely clear. As a term, evolution just means change over time. There are still some questions about how evolution happens: What are the underlying mechanisms, is there punctuated equilibrium, questions about how slow or fast it happens.

One big misconception is that evolution is this thing in the deep past—whereas in reality, evolution is happening all around us. If you think about agricultural crops, the things we eat, we are shaping evolution and evolution is happening all the time.

Rejecting evolution itself is just like being blind to the beautiful natural world that surrounds us. And if it weren’t for evolution by natural selection, we wouldn’t be here having this conversation.

Why is it important for people to understand evolution?
Because, first, we are the product of evolution through natural selection. The science has come so far, through both the fossil evidence and the genetic evidence, that we are really starting to understand our own human history in a fascinating way.

It’s been a journey of six and a half million years [of hominid evolution], with multiple evolutionary dead ends. We happen to be one little branch of that enormous tree of life that made it. We almost didn’t make it. It’s so important in understanding who we are.

Also because evolution through natural selection shaped the whole world around us. And of course we are intimately tied to the world and we are impacting it.

Take agriculture and the things we rely on for food and nutrition. We as humans have had an enormous impact by influencing natural selection. Through all the early attempts at agriculture and people selecting various traits, we’ve become a force in evolution.

We are also having an impact on evolution in terms of accelerating the rate of extinction. Many species would have gone extinct anyway, but I have no doubt that we are actually accelerating the rate of extinction of a bunch of species. In many ways, our activities are shaping the future of life on earth.

What are some of the studies being conducted by National Museum of Natural History scientists right now that give some of the most compelling evidence of evolution?
For almost all of the scientists here, if there is one word that unites all the work we do, it is “evolution.” It is the underlying concept of everything we’re working on. Not everything has to do with biological natural selection—we do deal with volcanoes and asteroids and other things—but evolution is one thing that really unites everything here at the museum. I would be hard-pressed to pick one because pretty much every research project we do is in some way connected to evolution.

But there are some particularly interesting examples we’re working on now. The work we’re doing in the Hawaiian Islands is really quite fascinating, especially the research coming out on the honeycreepers by Helen James and Rob Fleischer. The work includes not only birds alive today but also extinct birds. One of the wonderful experiences I had in May when I went to Hawaii was when Helen James took me into some of the lava tubes in the Big Island to find the bones of some of these extinct birds. It was amazing. We would walk through these dark corridors and see a pile of bones. When you date them, you find out that that particular bird died hundreds of years ago. And it’s very well preserved because of the airflow conditions in the lava tube. Between that and the genetic evidence, Helen, Rob and their colleagues have done a really great job looking at the speciation and extinction of the honeycreepers’ entire family. Hawaii is the American Galápagos, and honeycreepers are the equivalent of Darwin’s finches; it’s a very similar story.

Another example is one of our paleontology projects. We have one of the strongest groups of paleontologists in the world right now, which is wonderful. I could give 15 or 20 examples [of projects], but one of the ones I’ve been particularly interested in has been Scott Wing’s research in Wyoming. He’s looking at one particular point when there was a period of rapid climate change—except it happened 55 million years ago. This was when Wyoming used to have tropical rainforests. By studying this period you can actually see the environmental change. The beauty of the fossil record is that it allows you to travel in time, in one place. By comparing the different layers, you can see how the area went from a temperate forest to a tropical forest and back to a temperate forest in a matter of a few thousand years.

We don’t understand what caused the changes and why it became so much warmer, but it’s fascinating to see how quickly the vegetation changed, what survived, what came back and what went extinct. It’s like reading a book page by page, except that it’s a book that was written 55 million years ago.

A lot of what our paleontologists are focusing on right now is understanding those periods of rapid transition and understanding what triggered them and how the various groups of organisms lived.

A third example, which was a very special experience for me, is work in the field of human origins in Kenya by Rick Potts. My wife and I had a chance to go see the site about six years ago. It was wonderful to walk through that landscape in Olorgesailie with Rick and actually start reading the evidence. And it’s not just the human tools, it’s the entire landscape, the entire community that was there. You start finding teeth of zebras that have gone extinct and hippopotamus and other animals, and you suddenly realize that this entire landscape was really changing over time, from wet areas to dry areas, through a lot of environmental changes. And those changes were triggering a huge amount of variation and extinction and adaptation in all kinds of organisms—including early humans, but not only early humans. You can walk through a sequence that covers about one million years in a day. Going through there with someone who knows how to read that and interpret that, having a wonderful storyteller, is a journey back in time.

What destination did we miss in our evotourism package?
You should definitely include Hawaii at some point. We do a huge amount of research in the Hawaiian Islands and it’s amazing the data that’s coming out. You can really see evolution in action, probably even better than on the Galápagos Islands. Genetics has always been known for research on Drosophila and other organisms, but we’re getting a lot of interesting genetic research on the honeycreeper birds. You can go and see colorful birds like the Iiwi, and some of them are going extinct. Plus it happens to be a great tourist destination anyway, and you can see volcanoes in action. What was so striking to me in Hawaii was that everything comes together in that microcosm.

Laura Helmuth | | READ MORE

Laura Helmuth is the science and health editor at Slate. Previously, she was a senior science editor at Smithsonian magazine.