Thursday, November 8, 2007

Profiles in Biogeography: James H. Brown

Editor’s note: Dee Adams has interviewed rock icons from Janis Joplin to Mick Jagger. Jan Wenner is said to have dismissed Adams from the Rolling Stone for missing a deadline with the famously short message – “So long and thanks for all the interviews”. (Adams claimed to have thumb-typed the 27,000 word Van Morrison interview in a hotel bathtub and left the Blackberry in the soapdish. The file was never recovered.) Adams joins the IBS Newsletter as part of a court-ordered substance abuse and community service program, calling it “the ultimate cross-over interview challenge of my career”. Apart from our charity vocation, with this appearance the IBS editorial board wants to conduct an experiment on transversality and its true value in extreme cases. See Adams in action in this and future issues of the IBS Newsletter, with interviews of the icons of our field.


Profile of James H. Brown, University of New Mexico, Albuquerque, NM, USA.


Adams: How does it feel to be the ‘godfather of soul’?

Brown: Actually, I’m a biogeographer and ecologist.

Adams: Right, sure, (pause) what influenced the young James Brown?

Brown: I got my start in physiological ecology - trying to figure out how the limits on individual organisms translate into limits on species.

The role of physiology in the abundance and distribution of organisms is central. Climate regulates many physiological responses, which in turn influence distribution directly, and competition, fitness and predation that indirectly play a huge role in determining species ranges.

I was influenced by Robert MacArthur. I just happened to meet him, and he took an interest. He did that for several young ecologists whose ideas and work he thought worthwhile.

Early on George Bartholomew told me that you need to have one 'home' taxa to really understand ecology. I'd now add to that the need for one 'home' region as well. If you know one taxon and one region well, you begin to see patterns in the rest of the world. These systems that you are familiar with give you the confidence to work on other organisms and places and the insight into how to begin testing the broader patterns.

Adams: What makes James Brown (sings) feel good?

Brown: There is a rational reason we do conservation and there is a spiritual, or at least irrational reason. They're both central.

My interest in desert ecosystems came when my dad got a sabbatical in Patagonia Arizona. I'd grown up in upstate New York, but I'd never seen anything like the desert. Arizona trumped upstate New York every time, for me.

I always want to have mountains on my horizon. That's spiritual or visceral. I recognize those feelings and understand that they motivate my professional interests, but its important to realize that they are aesthetic and subjective and not to let them crowd into scientific judgment. Many philosophers of science would argue that division is impossible. Rational people can attempt it though.

I've heard that you tend to repeat what you do early in your career over and over again. I'd like to think that's not true for me. Serendipity is more important in my world. I like to try new things, follow interesting ideas and let them take me where they will. Its intellectual curiosity at the base - if you have it and follow it, it will take you some amazing places.

In conservation, my biggest rewards come from working with the Malpai borderlands group. This is a group of ranchers in the SW US that is dedicated to ecological restoration - to maintaining a healthy landscape. You can term that in ecosystem services or biodiversity, suit yourself, but at the end of the day it means a landscape that is more alive and vibrant than one managed just for profit.

In the Malpai, one of the big issues we're facing is the border fence. I am afraid this is going in whether we like it or not. Regardless of the broader issues, one local impact is that we won't have jaguars in the US any more. The US population is a sink at the moment and will never build into a self-sustaining population naturally if the fence goes in. So maybe this is a case where assisted migration has to be the solution. Its basically a huge experiment for large mammals. Some critters may be able to fly over it or crawl under it, but to jaguars its a wall. We either move them around it or they won't get to the US.

Adams: What issues should we all ‘get up’ about?

Brown: We're losing biodiversity on the big scale, no doubt about it. But on local scales, invasives and human commensal species may be increasing biodiversity. Does this mean that we have the wrong term (biodiversity) to describe our goal? -- I don't think so. Biodiversity is only part of the equation. Nativeness or naturalness has to be part of the metric as well.

So while invasives alter the local landscape, they may be over-rated as a threat. I refused to sign the Union of Concerned Scientists letter on invasives, not because I don't think they are a problem, but because I don't want to overstate the problem.

Habitat loss and climate change are much more serious than invasives on a global scale. The two together are particularly worrisome. There are some horrific invasives problems out there, and we need better ways to tackle them, but invasives are just not going to turn things inside-out on a global scale the way climate change and habitat loss will do and are doing.

Its just impossible to have 6 plus billion people on this planet and manage for 'natural' conditions that existed 200 years ago when there were a tenth that many people around. Managing to that standard is just a completely Quixotic exercise.

So what should we do? There's an increasing discussion about assisted migration to deal with climate change. We have to ask ourselves 'what do we want'. If nature doesn't hold the answer because we can't go back or the future will have no analog in the past, how do we decide on the goals for assisted migration?

Dov Sax is doing some really revelatory research into invasives. He's finding invasives increasing local diversity in places, without many associated extinctions yet. Looking at ranges of invasives in the arctic, these are close to the climatic limits of invasives in their native range. But in the tropics the match is much poorer. This suggests that biotic interactions (competition, predation, parasitism, and disease) are much more important as limiting factors in the tropics, while climate is more important in high latitudes. Is this a permanent situation or just a slower invasive process in the tropics? I don't think we have that answer yet.

Dan Simberloff and I got into a debate about a rodent paper we did. We used some data from the Nevada Nuclear Test Site to make a point about competition. Dan said, "so that means competition is more important than a nuclear bomb going off" I came back and said, 'yeah, that's right - fundamental principles of nature operate even in completely screwed up situations. I’m afraid that’s where we're headed globally - paradoxically, humans screwing up ecology on a global scale will reveal the really fundamental, powerful rules of nature that persist even when 'natural' is hard to identify. The really fundamental laws of nature don't stop because of human interference.

We'll lose lots of information about natural fine points as the planet becomes more dominated by humans. But the really powerful organizing forces of nature will endure, and biodiversity will recover from human insult. Granted, it may be a very different biodiversity than we know today, but natural rules will exert themselves and the long-term pattern of biodiversity gain will swamp the human setback in the end. What I'm more concerned about, especially for my children and their grandchildren, is the future for people. Can we put two or three times this many people on the planet and have them have reasonable equity, quality of life and respect for each other? I'm doubtful , particularly if we have a total energy transformation and planetary climate change in the bargain. We may exterminate ourselves or bomb ourselves back to the stone ages, but biodiversity will endure.

Adams: What about climate change?

Brown: The role of climate in species distributions is enormous, so the implications of climate change for biogeography are enormous.

Al Gore may have it right, a good analogy for global warming may be fever. Its a symptom of a deeper problem. The symptom can kill you, but if you don't get to the root cause, surviving the fever may not save you.

Biogeography can't be done independent of human geography any more. Like it or not, we've dominated the planet to the extent that there's no 'natural' baseline. We either have to have faith in natural processes to endure and will out, or admit that we've blown it.

I don't think we're losing species faster than we're documenting them, at least among higher organisms. There is a certain lore that gets out there because of the need to impress urgency on the general public. There is a biodiversity loss crisis and urgent action IS required, but we can't let that cloud the science.

A thing many people don't appreciate is that its not all that easy to drive a species to extinction if you don't hunt it. We have lots of examples of extinctions due to hunting. We're surprisingly thorough at that. But habitat loss, invasives, climate change - many species can hang on in the face of severe insult. Multiple insults may be a different matter, and we're waiting to see if climate change is the straw that breaks the camel's back for many species on the edge.

My ecophysiology instincts tell me that both speciation and extinction will go up with global warming. Things happen faster as temperature increases, its that fundamental. We may see startling rates of speciation as a result. That's biodiversity, but is it natural? We may need to start thinking about that distinction.

Ecological and economic sustainability - is that an assumption, hypothesis or oxymoron? In many international meetings its an assumption, but it may be a very poor assumption. There's very little data that tests this question as an hypothesis. So it may turn out its an oxymoron. Impacts displaced from one location usually turn up somewhere else. So as overall standards of living and population go up, impacts go up. Its hard to see sustainability in that equation if you're objective.

Adams: What’s your advice for young people starting out in the industry today?

Brown: If I was to choose a PhD topic today, I'd look at microbes. Friends looking at microbes in the oceans are finding 10 viral genomes for every bacterial genome. The numbers game on that is huge. We know almost nothing about these organisms or their ecology. That is the next frontier.

There was a recent NCEAS group on microbial biodiversity. We started by looking at how we'd class microbes using mammalian or phytographic methods, but then we asked, what if we analysed higher organisms with the methods microbial ecologists use? The answer was that the microbial ecologists call it a species when genetic divergence is 5% or more - that's the difference between humans and mice! The microbial world will change our perspective on biodiversity and how many species there are in the world.

If I had to guess the number of species in the world, I'd say a Billion or more. Most of them would be microbes, we're just scratching the surface of that facet of diversity.

A colleague went out to a meteor crater in New Mexico and pulled out genetic material for 400 species microbes. 387 of them were singletons. The genome of the most common soil bacteria wasn't among them. We have almost no idea of patterns of endemism in microbes, so how can we say they are cosmopolitan or have little endemism. What we can say is that there are unimaginable numbers of them, and we have no idea about their abundance or distribution for the most part.

The thing that intrigues me out of all biodiversity is the commonalities, not the differences.

To me, one of the most important things in my career has been the progress in data about straightforward patterns. For instance, when we did the first edition of the Biogeography text, we had no idea that tropical montane diversity peaked in the mid-elevations. We thought it started high in the lowlands and then dropped off toward the peaks, pretty much linearly. The data now clearly shows a mid-elevation peak. Its refreshing and encouraging to see the data speaking clearly like that.

Much of the future of biogeography lies in data as well. Data is now driving biogeography, as important as theory is. Databases now exist to address global issues and more are arriving every year.

Adams: Who do you listen to – who should I interview next?

Brown: What species would I look to for answers about biogeography?--I think blue whales or other great whales. Because they are still so little understood and play roles in the oceans that we probably don't fully understand. House sparrows would be next - they've established on so many continents, how do they see the world? We need to interview several populations - is every establishment the same or is each different in its own unique way? Finally, get inside the head of a microbe. What in the world governs the sub-visible? Even species definitions break down here.

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