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  • Writer's pictureMary Elizabeth Dawson

Nature’s Invisible Hand

Updated: Sep 4, 2021

A conversation with Paul E. Olsen. By Mary Elizabeth Dawson

Paul E. Olsen is the Arthur D. Storke Memorial Professor of Earth and Environmental Sciences at Columbia. Olsen currently teaches Dinosaurs and the History of Life, but his research focuses primarily on the evolution of continental ecosystems. He is particularly interested in mass extinction events and climate change. For this month’s Conversation, Olsen sat down with Mary Elizabeth Dawson to discuss everything from the Precambrian to the post-apocalypse.

The Blue & White: I just wanted to start with your history of getting into dinosaurs and studying them, because I remember from the very first lecture of the semester you had the picture of yourself at the World Fair and you were always interested in dinosaurs and I feel like I’ve only very rarely met people who knew what they wanted to do when they were young and then actually did it. So why dinosaurs?

Paul E. Olsen: It started basically with an interest in natural history as opposed to dinosaurs, but of course I loved dinosaurs, especially when I was really little. I remember vividly watching some TV shows, some movies on TV that I guess were fairly recent at that point that had dinosaurs, or something like dinosaurs, as their monsters, and I thought that was kind of interesting. I even remember having dreams about being chased by a dinosaur, or some version of that. But I really early on got interested in rock collecting and marine biology and all kinds of things like that, basically anything that had to do with natural history. I just kept following that as a kid. Arrowheads and rocks and fossils and shells and plants and pets—anything that had to do with natural history and science in general. I kind of liked mechanical things. I used to take things apart; in fact, when I was a baby, my nickname was “Knobby,” because I would go around the house and take knobs off of everything. I can remember being about two—I don’t remember being two, but I know I was two—and all the appliances being roped up so that I couldn’t open them.

Illustration by Rea Rustagi

B&W: I remember taking the door handle off the door in my room at one point when I was young and then not knowing how to screw it back in and thinking I was trapped in my room forever.

PEO: [laughs] Forever! Of course you did, of course you did. So, when I was in middle school, I did a lot of drawing. I was very involved in art, and I often drew things that were related to natural history. I remember one drawing in particular that I was thinking of recently that was a frog dissection, and I had devised a device—never built, but devised—that would recirculate its blood so that it wouldn’t die, because I thought that was a nasty thing to do. Although, somehow I guess dissecting it alive was okay! I didn’t think it through. In any case, when I got to middle school, I was very involved with having various fish, various vertebrate marine fish in tanks, and I converted my garage into an aquarium. I must have had 20 tanks going at a time, including some really big ones, hundred-gallon tanks, and I would collect a lot of my own specimens because I thought they were more interesting than these fragile little tropical things that kicked off if you looked at them wrong.

B&W: Yeah, I think I had like five Betta fish growing up, and I always got tired of them and kind of ended up waiting for them to die.

PEO: [laughs] Yeah, yeah. But I got interested enough that I wanted to build a submarine, and in middle school I started doing that. My metal shop teacher was very kind and let me actually build the frame in the metal shop. I actually finished the hull, more or less, and then I started hearing about—I was still interested in fossils—and I tried to convince my parents to let me go to the Gobi desert, and that didn’t work out because of the Cold War, but they did take me to Europe when I was eight, and we went to museums and places like that. It was very interesting. They always took me to museums, and I think that’s how I developed the core of my interest in paleontology. I do remember going to the American Museum of Natural History specifically and how much fun that was. So many people in science were influenced by going to these museums and seeing the fossils, and I was one of them. So, while I was working on my submarine, a newspaper article came out in the local paper, about a fossil footprint being given to the local library in Livingston, New Jersey, and it had been found in a quarry near my house. I thought, “Oh boy, I’m going to go out there,” and I grabbed one of my friends, Tony, and we went out, biked out a mile or so from my house, and there was this quarry, and there were amateurs already collecting who showed us what they were finding and how to do it. We befriended one of the guys, a guy named Bob Salkin, who was very encouraging, and I met him multiple times after that. He showed us what to find, and we started finding dinosaur footprints immediately, within minutes. That’s rather characteristic of that rock, not our skill. The footprints are so common that anybody with even a tiny instruction of what to look for and how to look for it can find it in minutes. That, within a year, completely diverted my attention from the submarine, which my parents were incredibly grateful for.

B&W: Yeah, I bet. Better to look for footprints than build an entire submarine.

PEO: Which you are then going to take into the ocean and use, right?

B&W: So, the place where you found the footprints was the Riker Hill fossil site, right?

PEO: Yes, that was the Riker Hill site.

B&W: I actually have a question about this. How did you go through the process of getting that site established as a National Natural Landmark?

PEO: Yes, so, you did some Googling, obviously.

B&W: Yes, and I think you also mentioned it in class at one point.

PEO: That’s right. I cannot claim credit for originating the concept or having the wherewithal to follow through. However, one of those amateurs, actually Bob Salkin, was an educator in the New York public school system, and he used dinosaurs as an avenue to get underrepresented, underprivileged kids to read and write and do drawings and so forth. It was a very effective program, which he did for most of his life. He was a metal shop teacher, interestingly enough, but he was really interested in fossils and devoted himself to those public education efforts. He had been involved in a project to try to preserve another place in New Jersey where dinosaur footprints had been discovered called Tom’s Point in Lincoln Park, and that failed and became a golf course. He thought it would be a good idea to try to preserve this place too, but he had learned that direct ways of doing that simply would not work. He had a friend at the Newark Star-Ledger, which was a very well-read newspaper at the time, who had a different kind of plan. So Salkin thought that he could engage us to do the effort so that it would be kids trying to drive this thing rather than just adults, and that proved, in fact, far more effective. I was very willing to do this because I also thought it should be preserved. He, through his friends who were involved with the Newark StarLedger and other educational things as well, made sure that we got some publicity starting right off the bat. Eventually we were attending town hall meetings and getting lots of people involved. There were quite a few local people who also got involved in the town to try to preserve it. Strangely enough, the one group we never contacted was the actual owners, who turned out to be a very large company called Walter Kidde & Company, and they eventually called me—I remember this vividly, sitting in the kitchen on the phone—and they said, “You know, you never actually asked permission to do any of this stuff. Don’t you think it’s not right that here you are, asking us to donate this property, and we never gave you permission to do that? We think that you should stop doing that.” That’s what they said. But, that’s when the publicity for this was kind of getting going. I got a call two days later from Life magazine saying that they were going to do a story. I said, of course, that they should speak to the owners by that time. Somebody at that company [Kidde]—a publicity person—realized that this would only be negative coverage for their company, and they realized that, in fact, at least half the property was very difficult to develop. It was on a very steep hill, and if they donated that, they would get a tax write off on that part of the property, and if they kept the other half, they could develop the lower part for condos, as it turned out. They announced that in time to take advantage of the Life magazine article, and hence, “The dinosaurs finally win one” was the title of that, and it became a huge success. In the meantime, prior to that, I wrote the National Parks Service, the Essex County Park Commission, and ultimately Richard Nixon. I got a nice reply back saying, “The President is very interested in hearing from you, but very busy,” blah blah blah blah. What I didn’t know was that right next to the quarry was a light industrial company called Kidde Precision Tool, which was a separate company than the company that owned the land, although connected at some deeper level. Kidde Precision Tool had a Vice President of Public Relations named George Green, and Mr. Green took an interest in us and helped us in getting soda and tools and things like that, and there was no bathroom at the quarry so we could use the facilities at this light industrial plant that was really right next to it. He was really nice, and what we didn’t know was that he was writing President Nixon. He was a staunch Republican supporter, and he wrote Nixon saying, “Wouldn’t it be a good thing if you had the boys visit you in Washington and showed America what the good youth of the United States looked like?”

B&W: The good youth. That’s funny.

PEO: Well, at that time, we were involved in Vietnam and there were protests all over the country. Kent State had just happened. So, this was was a big deal, the protests, and the youth movement was a really big thing in the late 60s. There were drugs and the whole “Turn on, tune in, drop out” business, so he thought by getting us to the President that this could be a publicity thing. And it turns out that there was a massive amount of communication between the President’s staff members about this that, in fact, involved almost the whole high-level Watergate group. Haldeman, Ehrlichman, they were all involved in this discussion about these two kids. Meanwhile, they’re invading Cambodia! Obviously there was an attention span issue here. They’re spending all this time—which I didn’t learn about, by the way, until 2008… Finally, William Sapphire, who used to write for The New York Times but before that was a speech writer with Nixon and was one of the group that was involved in this discussion, said, “No, that shouldn’t happen because of the inevitable jokes about the Neanderthal Wing in the White House.” Instead, after the article in Life magazine came out and after the company said they were going to donate this land, Nixon sent a presidential commendation to Tony and I for our efforts in trying to have this converted to a park. The National Natural Landmark status came about immediately thereafter, and by that point I was going to Yale, which I only got into because of my fossil efforts, because my grades were truly hideous, and because of the professional friends I’d made inside the community through the efforts of Bob Salkin. We were, in many ways, being used by well-intentioned older people to further their agenda, which was mostly my agenda. I wouldn’t have known how to do that. So, it all worked out quite well. Even Nixon got something out of it. Not much! But a little bit.

B&W: Do you think it’ll ever be developed?

PEO: I think so. It’s a good resource for the region, but it has to overcome the inertia that’s been there for a while, and I haven’t been focused on it, certainly.

B&W: I wanted to move on into what you’ve been researching and studying more recently, which is focused on mass extinction and climate change, as I understand. This has obvious connections to dinosaurs, but why teach a class on dinosaurs instead of a class on climate change?

PEO: So, I do work on dinosaurs, I work on dinosaur footprints, I’ve published on that, I’m writing a book on it. It’s certainly not my major area of research. I have contributions I’ve made, and I think they’re important ones. I have another one in the mill on how dinosaurs took over, but my basic research focuses on climate change, mass extinction, and, oddly enough, celestial mechanics. The reason I started teaching the dinosaur course goes back to when I was first hired at Columbia … I discovered when I came to Columbia that I was basically expected to be funding my own graduate students … I did some digging into funding, and I discovered that, at the time, our department would receive a certain number of graduate student fellowships from Arts and Sciences based on, in part, the number of undergraduates we were teaching. I thought, “Well, I could do something about this … I can make a contribution indirectly to graduate student funding by engaging undergraduates in an attractive course.” The second point of this is that I was recognizing, at the time, that people were coming from Columbia, going into politics or going into law or whatever, and had basically nothing but bad contact with science. All of their contact was unpleasant.

B&W: Right. I think there’s definitely a lot of people at Columbia like that.

PEO: And they had structured their high school career to very carefully navigate around to avoid taking classes in which they would do badly and therefore hurt their chances of getting into a prestigious college. This still goes on. It’s a real problem, because the very people that end up being in local to national leadership positions are some of the very people who have avoided that contact. So, I tried to do something about that, so I started this course on dinosaurs. As a student you may have noticed that I constantly refer to how things are done, how do we understand this, what does this mean, how does this intersect with current things going on. The idea is, and I say this in the preamble to the course, that it’s an attractive way to get undergraduates involved with science. It’s a ready portal, there’s some framework already there, you can get into it without any prior information, and even for people who have science backgrounds, cladistics for example, they don’t have any experience with that. It’s a completely different way of thinking.

B&W: In further relation to your studies on climate change, at this point, how are you feeling about the future of the environment and the hypotheses that we’re at the cusp of the next great extinction event?

PEO: Let’s start with the extinction event. That’s well underway. If you look in the fossil record, humans have basically wiped out almost all large mammals. The only ones that still exist are really endangered. There are two species of living elephants, maybe three, some people like to split off some varieties, but there are certainly well-accepted species of elephants, the African and Asian elephants. Those are the largest mammals that are on land, and they’re endangered. Whales are clearly endangered. If you looked at the fossil record, you’d already see that a mass extinction is happening. These large mammals are in many cases keystone species that structure environments. We’re not familiar with what North America would look like with these mammals around. We know from fossil evidence that, were we, as modern human beings, to look back at what things looked like before mammoths and mastodons and giant ground sloths and giant armadillos that lived in this region went extinct, we wouldn’t recognize the area. Even pristine areas, “pristine” in quotes, looked more like a chaparral than they did a forest. Eastern North American forests are a modern construct that date since the extinction of large mammals in North America. They would have been much more open and had much more grass than present, modern forests. There are a whole bunch of smaller species which relied upon those large mammals to structure the environment, and many of those are endangered or even extinct. That extinction’s already happened. Now we are endangering enormous numbers of species by habitat loss. That’s the principle mechanism by which species are being driven to extinction. Almost all those species will not leave a fossil record, so future paleontologists wouldn’t even recognize those extinctions. Also, most species exist in very small numbers and in very localized areas, so those just would disappear without any record of them ever existing. Not a very cheery thought, but that’s the way it is. Even in our efforts to preserve habitats, there is a whole issue of whether island habitats are actually successful in maintaining their diversity or not. I would guess no, they’re not, because things are changing very rapidly. They change naturally very rapidly, but we’re accelerating them in a directional way. Even without human intervention, climate change happening on a random basis would result in decades of drought happening naturally and result in these island habitats becoming uninhabitable for certain species, and that would be their end. So, I believe that mass extinction is already underway. We would look to the future, if we were paleontologists looking at what happened after this mass extinction, and see a different history. Smaller animals would give rise to larger animals in the future, with or without us. How that’ll work out, who knows. We don’t know which animals will be successful. We know which animals are successful in our presence, but those aren’t necessarily the ones that would give rise to other forms in the future, they may just continue happily the way they are. Blue mussels are incredibly successful in the oceans. They haven’t given rise to giant blue mussels.

B&W: One thing you just touched on, human intervention contributing to climate change, I discussed in my research paper [for your class]. I find it really interesting that this is the first time one of the primary driving forces of climate change, which is humans and human actions, has been a sentient force, something that can comprehend the implications and consequences of its actions. What do you think about that? Is there a significance there?

PEO: Oh, there’s a big significance to the fact that we’re the only species that has existed on our planet that knows what it’s doing. We can predict the outcome of our actions, and we can understand them, and we can change or not change in order to mitigate or not those results. We are not the first species to have massive effects on climate. We’re far from it. In fact, our effects on climate will be relatively minor compared to the number of evolutionary events that have happened in the past. For example, the invention of oxygenic photosynthesis, which gigantically changed the planet in much more profound ways than anything we’re planning on doing. In retrospect, we think that was a good thing, but if you were an anaerobic bacterium, you would disagree. That was a bloody disaster! It made nine tenths of the earth uninhabitable, so that’s an enormous change. Forests changed the world tremendously. The ability to live on land, free of water—open water—was an enormous change, again, to organisms that were around. Many of them, if they could have, would have thought it was a disaster, but it was an enormous biochemical change, far greater than the change we’re doing now. Our change in climate is in a direction that the Earth is used to, if you will. Most of Earth’s history has been spent in the non-glacial period, so the current climate that we have is not normal for the Earth. You could even take the point of view that we are bringing it back to normalcy. However, our effect is temporary at the scale of tens of thousands to hundreds of thousands of years because, sooner or later, our fossil fuels will run out, and then we will cycle back to the situation in which we were beforehand. The oceans will absorb that carbon dioxide and the pre-industrial climate will reestablish itself, we think, although that’s not necessarily the case. Sometimes climate change produces changes that aren’t reversible, in the sense that they change the climate state and it’s in a new mode that’s stable until something kicks it over in the other direction. So, something kicked the planet over into the Ice Age mode, which it hadn’t been in for 300 million years before that—more like 350 [million], actually. We think that kick was a rather steady decline in carbon dioxide levels to the pre-industrial levels, which at some point caused the northern hemisphere glaciers to start cycling on and off, and the antarctic glaciers started quite a bit earlier than that. Again, the carbon dioxide levels dropped below a certain threshold.

B&W: So, do you think a complete extinction, or at the very least a severe bottlenecking event, of humans is plausible or possible?

PEO: No, I don’t think climate change as driven by human beings would produce such a bottleneck. Warfare related to that climate change could do it, pretty easily, as a matter of fact, if not result in the extinction, but that’s actually fairly unlikely. Humans are very resilient and very inventive. Even with nuclear war, survival is plausible, but that would create certainly a bottleneck. What is quite likely is that climate change—it’s not just likely, it’s happening—results in stress for populations that are already under stress and makes things a lot worse. It triggers migrations, migrations cause instability, political problems that can result in warfare and that can cause mass mortality. Related to that—and related to our large and fluid population—could be large epidemics. The combination of an epidemic plus a very stressed population could lead to very significant deaths and, again, population bottlenecks. Although, even with things like the Black Death and Influenza—the early twentieth century Influenza outbreaks—they have not caused the kinds of bottlenecks that humans have experienced before when we had much, much smaller populations. It does result in natural selection, which does modify the population, and this is probably why we don’t suffer from that kind of Influenza outbreak that occurred before, because the strain is still around. So, yes, I do think bottlenecks are possible, but not as a direct result of climate change. You could argue that the percentage of arable land will actually increase as a result of global warming, but not in the same place that we have agriculture now and that change is occuring, so it’s definitely stressful. To animals that are already in habitats that are restricted, and plants, it will probably result in extinction of those groups. Many species, by the way, could be replacing those in relatively short order, so it’s not necessarily that those organisms like insects and things which provide most of the diversity on earth that may not produce a visible change in diversity when viewing a fossil record.

B&W: So, I remember a while back reading something and the author was talking about a new form of environmental nihilism where people have started to say that the earth is so screwed up and the environment is so screwed up there’s nothing to do at this point … The author continued to make the claim that this view was just as dangerous and detrimental as that of people who completely deny that climate change is even happening. So I was just kind of curious about what you think about people who are thinking that way.

PEO: It’s an interesting point of view that harm has already occurred, and we can’t do anything about it, so why bother, but it is true that we’re already down the path of enough carbon dioxide to significantly change the climate. However, that doesn’t mean it won’t get much more dramatic if we continue along our current path. Now, it’s clear that adaptation— resilience is often spoken of—will be necessary. We need to be able to deal in practical ways with climate change that is happening and will continue to happen regardless of what we do. But the fact that it’s going to continue to happen no matter what we do does not mean we shouldn’t stop making it worse. Right? And it can get much more dramatic. Now we’re expecting some significant sea level rise as a result of current climate change, but you can deal with it in the same way Holland has dealt with high sea levels by building dykes, moving populations inland, and so forth. But, if the ice caps were to melt, which is not impossible— in fact, in 2400, beyond the scope of most people worrying about—if the current increase in levels of carbon dioxide continues, we’ll have levels of carbon dioxide about 4,000 parts per million, which is at the level at which in past times that we had no ice caps at all, and sea levels would rise over a hundred meters. At those conditions we would lose entire states, like Florida. Gone. Completely underwater. Whole levels of Asia would just be completely underwater. Now, of course, at the rate at which that could happen, would humans be adaptable? Yes. We would. In terms of the whole earth’s history, high carbon dioxide levels themselves are not necessarily bad at all. You could make the case that eliminating the ice caps and [having] high carbon dioxide levels are much better for life, on average, than our current situations. The entire polar regions are uninhabitable now by most large forms of life. Period. That’s not normal. That’s a significant reduction in area that’s viable for life on the planet, advanced life on the planet, complex life on the planet. So you could argue, at the biggest scale, undoing that is a good thing. However, like I said, we will exhaust our fossil fuels or at least bring them down to levels that you couldn’t pump carbon dioxide into the atmosphere. By 2400 we’ll be certainly in that territory. So what happens then? Then it goes back, right? So then you’ve got the ice caps and you’ve had a mass extinction, so that’s really… I mean if you think a lot of life is good, that’s not good. These are value judgements, they’re not scientific opinions, they’re not scientifically based ideas, but if life is good, then that’s bad.

B&W: That’s interesting. I’m trying to wrap my mind around it.

PEO: It’ll be great for organisms, and by 2400, you’ll have significant advances of forests into the arctics and arctic regions, but then again, when carbon dioxide starts lowering in 400,000 years, which is how long it’ll take for that carbon dioxide to come out of the atmosphere, the ice caps will come back. Of course they’ll come back probably to greater extent than they were before that because the trend to lower CO2 globally will still probably be maintained. By the way, why CO2 has been dropping is not understood in a very basic way. Why did CO2 drop 350 million years ago? The leading idea is that it was due to the spread of land plants. Why is it dropping now? One leading idea is the growth of mountain belts, but another possibility is that the growth of grasses as super plants, they may be shunting much more of the carbon dioxide, also through fertilizing the oceans into sediments and thereby on a very long trend, by their own diversification, lowering CO2 globally. They will still be around when the effects of humans on CO2 are not, and that will result in even lower carbon dioxide levels. At what point that stops, we’re not sure. There are even scenarios in which we could trip back, because of the action of life—not us, but because of other organisms—into the snowball Earth condition that happened several times, we think, in the Precambrian. The entire Earth was covered with ice. That is surely not good for higher life forms.

B&W: It seems like everything is so cyclical.

PEO: There are cycles, but there are also singularities. Evolution produces dramatic singularities. Inventions of life forms that do things with their metabolisms that nothing ever did before and take hold of the Earth’s climate and metabolism and basically completely take over. This has happened multiple times, and it will happen again. But, the results are not what we would call good for everybody around.

B&W: I remember at the beginning of the semester you had mentioned that you were working with celestial mechanics, and I feel like some people laughed because they were thinking, “What does that have to do with anything you do?” I was definitely thinking that.

PEO: Right, right. The thing is, about science and geology and paleontology and sedimentology, they’re all related, and they’re reflecting things that we think really happened. They tell us things about our world and our universe that we wouldn’t be able to get any other way.

B&W: Yeah, I think it’s really fascinating. Okay, well, I wanted to end on something light. Do you have a favorite dinosaur?

PEO: Do I have a favorite dinosaur? That’s kind of like kids, you know. Which is your favorite child? Do I have a favorite dinosaur? It’s a very difficult question. Actually, I do have a favorite dinosaur. It’s a parrot. Although presumably you mean a non-avian dinosaur. I like those strange dinosaurs we saw in the Jurassic—a class called Scansoriopterygidae. The dinosaurs that have a web of skin as a wing, instead of feathers. That, I think, is superbly bizarre. I think that is really, really out there. Right now, that’s my group of dinosaurs du jour.

B&W: I’m thinking about it. It’s kind of like a bat-dinosaur.

PEO: It’s a bat-dinosaur! That’s exactly right, it’s a bat-dinosaur. Now, it’s conceivable that that interpretation is wrong, because the membrane that’s supposed to be the wing is not all that well-preserved, but it has this extra bone that extends way out of its wrist, and it’s really hard to imagine what the heck that thing’s for, except to support a membrane.

B&W: We’ve looked at a lot of things in class that are just so, so weird. And you just kind of have to speculate why they were there and what they did.

PEO: Right, right. Well, a platypus is a living animal and it’s…

B&W: It’s weird.

PEO: Yeah. Really weird. And you probably wouldn’t guess that it has venom, but it has a spur on its leg that has venom. And you wouldn’t guess that its nose is electric, either. It has electrical receptors, and it snarfs around for food in lakes using electricity.

B&W: Whoa, I didn’t know that. Nature comes up with some weird stuff.

PEO: It sure does. Whatever works! That’s basically nature’s motto—whatever works.


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