Integrating the Social Sciences with the Environmental and Earth Sciences

Seven years ago, I was invited to participate in a panel at NIH in Bethesda charged with evaluating the joint NSF/NIH interdisciplinary program on the Ecology of Infectious Disease. While there was an explicit call for the participation of social and behavioral sciences in the call for proposals, very few social scientists were getting involved in this remarkable program. Having participated in a wide array of similarly interdisciplinary panels, I knew that this was a common dilemma: the architects of the panel (whether it is a panel evaluating grant proposals, an interdisciplinary symposium, or an edited volume), who are typically natural scientists of some sort, make a good-faith effort to bring social scientists into the fold, but generally have little luck. Through a series of slightly hilarious miscommunications and travel snafus, I was unable to attend the meeting in Bethesda. I holed up for a weekend in a cottage in Santa Fe (where I had been participating in an panel the previous week) and wrote a document on how researchers working on the ecology of infectious disease could engage the social sciences and social scientists. As I contemplate my new role in the School of Earth, Energy, and the Environment at Stanford, it seems like a propitious time to revisit this white paper.

The stakes for involving the social sciences in environmental research – broadly construed – are high. Massive – potentially existential – problems like climate change, emerging pandemic disease, and large-scale extinction have both human drivers and enormous consequences for human welfare. This said, there are precious few social scientists – people charged with understanding human behavior and societies – who are engaged in research on environmental problems. This problem is particularly acute at elite institutions such as leading research universities.

Since human behavior is central to many aspects of most environmental problems, the contributions of social scientists to work on environmental problems is important and, quite possibly, necessary for dealing with the major problems associated with this domain of research. Understanding environmental problems such as climate change is obviously of major significance for state actors (e.g., governments, regulatory bodies)  and, ultimately, people more generally. Why then is it so difficult to engage social scientists in these research questions? This seems all the more puzzling given the amount of money potentially available for this research, particularly when compared to the funding available within the social science disciplines. There is clearly a collective action problem here: the generation of a public good that could come from the cooperation of social scientists and natural scientists is being inhibited somehow. Presumably, there would be benefits for social scientists who chose to collaborate with natural scientists on important environmental problems. Why then are we stuck with the collective action problem?

Sometimes, there is an explicit attempt to get social scientists to do the bidding of natural scientists in promoting social or cultural change for their desired ends. The eminent Stanford ecologist, Paul Ehrlich  has called for research into the mechanisms that change social norms, suggesting that there is an urgency to changing norms because of mounting environmental problems. The irony here, of course, is that in trying to engage social scientists in research on the environment, Ehrlich and other interested natural scientists needs to induce a change in social norms.

In an essay reviewing models for changing social norms,  Ehrlich and the great Princeton ecologist Simon Levin note that they did not even attempt to address how asymmetries of power or social networks affect the spread of social norms. Unfortunately, this is exactly the problem facing natural scientists trying to engage social scientists and models that fail to acknowledge these factors are doomed to failure. Within both the academy and society more broadly, there are distinct power asymmetries across scientific fields and, in general, social science fields are on the losing end of such power asymmetries. The great majority of social scientists can not compete with natural scientists with respect to research funding or the prestige (or volume) of of their publications.

When power/prestige gradients are steep, disciplines are likely to become insularized. An adaptive response to a collective’s inability to compete across disciplines is to, consciously or not, collude in agreeing that the only relevant opinions about the quality/volume of individual scholars’ research are other members of the scholars’ discipline. There are institutional practices that can facilitate this (e.g., the manner in which promotions are managed). I suggest that insularized disciplines will also fetishize theory above all other intellectual outcomes. Theory becomes fetishized at the expense of answering interesting and important questions or developing new methodologies for answering important questions. There are few checks on the degree to which theory can become abstruse and convoluted when its development becomes decoupled from answering questions. There comes a point where only very narrow specialists can ever hope to understand the intricacies of a particular theoretical tradition and be successful. Emphasizing theoretical development above all else within a discipline is thus a path toward disciplinary insularity and is the enemy of both interdisciplinarity and problem-focused research.

Social science disciplines do not gain prestige or other within-field benefits from engaging in the substance of human-environmental interactions. This arises in part because of the dynamics of differentiation from higher-prestige science disciplines engaged in these questions. There is also a positive feedback. Way back when I first came to Stanford, I was at a party where most of the other party-goers were political scientists. At the time, I was struck by the fact that there didn’t seem to be anyone in the department who studied environmental politics. I took the opportunity that this party afforded to ask a fellow assistant professor in that department why this was the case. His answer was simply “because no one could ever get tenure at Stanford studying environmental politics.” This conversation piqued my interest and I have now had a similar conversation with quite a few economists and political scientists. While not everyone is as blunt as my interlocutor in 2003, most have agreed broadly that working on environmental questions is not the route to professional advancement and these topics are therefore avoided by promising junior scholars trying to forge research careers.

I should probably note that economics provides an interesting exception to the power/prestige hierarchy. It’s really a topic that deserves its own post, so I won’t get into it too much here, but I think that economics is an exception that proves the rule. While the discipline is certainly more prestigious than, say, anthropology (!), I think that it’s hard to imagine a more insular discipline that fetishizes theory – and its mathematical accoutrements – more and in which professional incentives are absolutely not aligned with the interests of interdisciplinary, problem-based science.

Another phenomenon that has become a barrier to genuine interdisciplinary engagement for social scientists is the tendency for scientists from high-prestige disciplines to dabble in social science. The hilariously half-assed surveys that some scientists field when they want to get at the “human dimensions” of their problem come immediately to mind.

At a more structural level, I think about network science. When one attends the Sunbelt Social Networks Conference, one can frequently hear grumbling about how a bunch of physicists have swooped in and created what is sometimes known as a “new science” of networksIt is rare to find citations to the substantial social science literature on the topics many physicists write on other than the token citations to Milgram or possibly Simmel. New terms for well-described phenomena are invented and go largely to cultural fixation. Prior work (often 20 years old) is ignored. Papers on social networks get published in Physical Review D rather than established technical journals like Social Networks, Computational and Mathematical Organization Theory, or the Journal of Mathematical Sociology. Within-discipline citations are circular. Concepts having little interest to social scientists (for good reason) go to fixation and demand being addressed despite dubious relevance (e.g., “scale-free” networks).

I am actually of two minds about this phenomenon. On the one hand, it would be nice if this “new science” did a better job acknowledging that smart people have been working on these topics for quite a long time. On the other hand, I think that we need to have more more than the small handful of methodological innovators who work on social network analysis from within social sciences departments. The volume of quality work coming out of the physical sciences is almost certainly greater than that coming out of social science departments. A big part of this is the social organization of science (see below), but surely part of this is about getting smart people to work on important problems. We need to have more social scientists who are willing to engage in the general science literature where the visibility is greater (e.g., compare the citation patterns and general visibility of Science vs. CMOT!). Social scientists need to be willing to take the risk of publishing their strongest results in high-prestige general science journals like Science, Nature, PNAS. Yes, we will usually get rejected, but that’s no different from the experience of natural scientists, and we are certain to never get into these high-impact journals if we never even try.

I do not, in any way, want to decry the engagement of high-prestige natural scientists with the social sciences. Indeed, this is something we desperately need! But it needs to be real engagement rather than either dilettantism or intellectual imperialism. Three examples of physicists who switched disciplines and had enormous positive effects come immediately to mind: Harrison White (Sociology, Columbia), Bob May (Epidemiology, Ecology and Evolutionary Biology, Oxford), and my sometime mentor, Shripad Tuljapurkar (Demography/Population Biology, Stanford). These are all scholars who took the substance and the history of their new disciplines seriously and have made enormous contributions. My amazing Ph.D. student Mike Price is a physicist-turned-anthropologist who is poised to make some truly fundamental contributions to anthropology, evolutionary biology, and economics.

A key issue that has not been sufficiently addressed in the differential funding, productivity, and status within universities is the social organization of science. The natural sciences are generally structured for productivity: organized labs, large groups working toward a common research goal, substantial division of labor. This social organization of science certainly interacts with institutional structures. For example, the allocation of teaching load and the manner in which activities (i.e., lab meetings, co-taught classes) are credited often differs systematically between the natural and social sciences. For the most part, social scientists still follow a more individualist model of scholarly production. Papers may be written with students, but research groups, if they exist, are not necessarily structured for production toward a common research goal. My own situation is instructive on this topic. As an anthropologist, I have always had more of a natural-science culture to my research group. This said, my “lab” has always been more a loose confederation of people more or less interested in similar things, than a group focused on a clearly-articulated research goal.  There was a point not that long ago when I had Ph.D. students simultaneously working on the following topics:  bushmeat in Cameroon, sex workers in China, malaria ecology in the Colombian Amazon, water security in Caribbean Colombia, sago horticulture in West Papua, disease transmission networks in Uganda, rodent population cycling and hantavirus transmission, TB in South Africa, food sharing in Nunavik. Now that I’m based in a natural science department, there is hope for some more coherence.

Really Inviting Social Scientists to the Table: A Power-Inversion Strategy

We have a situation where lower-prestige disciplines effectively opt out of competing with high-prestige ones, where runaway theory fetishism institutionally insulates scholars interested in similar phenomena from each other, and where substantive applications to problems of human-environment interaction are institutionally blocked. How do we get social scientists engaged?

The simple answer is that professional incentives of social-science researchers (particularly junior ones) and the institutional and societal priorities of solving vital problems involving the environment and human well-being need to be aligned. The first step is to get social scientists to the table to foster an environment of collaboration. Being mindful of the power dynamics across fields, collaboration opportunities need to be framed in terms of categories of thought and research questions of intrinsic interest to social scientists.  This may sound trivial, but it is key that this framing be consistent with the autochthonous development of ideas within the social sciences, rather than (even well-intentioned) natural scientists’ conceptions of what social science is. Even though an RFP or other invitation may seem like something in which social scientists should be interested to natural scientists and program officers, it may not obviously address institutionally important or interesting questions, theories, or methodologies from the social scientists’ perspective.

Remember, the system of professional reward works reasonably well from any individual social science researcher’s perspective. We expect agents to be risk-averse and such risk-aversion in this context leads to the collective action problem that we are forgoing a public good of increased understanding – and maybe even the ability to positively intervene in – significant environmental challenges of humanitarian, social, and economic import. By framing questions in terms of existing research themes in the social sciences, we may be able to overcome the risk-aversion because properly framed research opportunities should not be professionally risky.

Some areas within social science of relevance to the environmental sciences include:

  • political economy, global-to-local political relationships, the development of power asymmetries – particularly in regard to access to resources, health, etc.
  • equity, justice, property rights, and social movements
  • trust, governance, conflict
  • consumption, social, cultural and symbolic capital
  • institutions
  • migration, indigeneity, and ethnicity
  • markets, commodities, motivations, values and cosmologies, and time horizons

In brief, if we want social scientists to become engaged with research generally seen as beneficial from a societal perspective, we have to let them “do their thing” first and let the natural science do the complementing. Rather than asking how social science can contribute to natural science research agendas, we must sometimes ask how natural science can contribute to social science research agendas. Some examples from infectious disease ecology: How can thinking about the emergence in the western hemisphere of Zika virus help us understand the development of trust or its implications for governance? How do neoliberal economic policies promote the emergence of Nipah virus of Japanese encephalitis? Why does the Indonesian government refuse to provide H5N1 samples to the US CDC or WHO? This certainly doesn’t mean that it always has to work this way, but it must work this way sometimes if progress is to be made.

I do think that natural scientists and social scientists need to be able to sit down and put together intellectually strong, multi-disciplinary research projects together. However, the way to get social scientists engaged in the first place is to frame the research possibilities in terms that are relevant to them. From here, real interdisciplinarity can be achieved.

New Ebola Paper

OK, not exactly new new, but certainly newish. This post is part of my new attempt to update my blog more with stories about science, research, and education in an attempt to avoid the vicious cycle of anxiety and depression that comes from spending too much time reading the news and engaging in social media.

Our paper on the prevalence of asymptomatic Ebola cases in Sierra Leone was published in PLoS Neglected Tropical Diseases on 15 November. In it, we show that nearly 10% of a sample of people from an Ebola hotspot in Kono District, Sierra Leone, tested positive for Ebola virus antibodies despite having reported no symptoms of Ebola Virus Disease.

The West African Ebola epidemic of 2014-2015 was the biggest outbreak of the disease ever recorded, with over 28,000 reported cases.  Our results suggest that the total number of cases may have been quite a bit more than this. They also suggest that Ebola is, as we suspected, like other pathogens and causes a wide variety of clinical manifestations.

The paper received quite a bit of media attention from outlets such as NPR, The Wall Street Journal, The LA Times, and Gizmodo.

This work was led by my rock-star Ph.D. student, Gene Richardson and involved a great many collaborators.  It was a great honor to be able to publish with such luminaries as George Rutherford, Megan Murray, and Paul Farmer. With several papers in the works or already submitted and ongoing research, I’m really looking forward to more results in the near future!

AAA Post-Mortem

Well, it’s been a long time and there are bunch of things I should really catch up on here. I spent last year on sabbatical in the very remote location, at least half a mile from my house, of the Center for Advanced Study in the Behavioral Sciences, where I was working on various book manuscripts that seem to grow in number the more I write. Then there’s the fact that I changed Earth Systems Science. This is a topic that clearly requires a bit of explication at some point, but now is not the time. I figured I’d break back into the blog by doing my semiregular, highly-selective review of the American Anthropological Association meetings.

The meetings this year were in Minneapolis, which is a lovely city, but maybe not the best place for a conference that meets in mid-November. Apparently, the weather was beautiful for the first couple days. However, I had spent the beginning of the week in Atlanta at the meeting of the American Society for Tropical Medicine and Hygiene (that was a very interesting meeting, but this post is about AAA). This meant that I had to fly in late Friday evening before my Saturday session. By this time, the weather had changed to something slightly more horrifying. While my flight seemed like a relatively long-haul (4.5 hours from SFO), we nonetheless flew in a regional jet. A storm had moved into the Twin Cities area by Friday afternoon and our little plane got tossed around quite a bit in our approach to MSP. In fact, we flew in a holding pattern for about an hour before the pilot came on intercom and said that we “we’re going to try to land” Try? It was a white-knuckle landing in which we experienced more yaw than I care to remember. There are many reasons that I’m grateful that our try at landing was successful, and high among those is the fact that I didn’t relish the thought of climbing back through that unsettled air if we had failed on our first pass.

Once safely on the ground, I was able to take the lovely (and cheap!) light rail straight to downtown, about three blocks from the conference venue. I don’t know what one calls the precipitation that was falling at this point (sleet? freezing rain? wintery mix?), but it was quite a shock for this adopted Californian.

The meeting was held in the Minneapolis Convention Center, a cavernous space that the 5,000 or so anthropologists didn’t come close to filling. This gave the conference a bit of a ghost-town feeling. Adventitious encounters were minimal and I definitely saw far fewer anthropologists of different stripes than I have at past meetings. The registration process was surprisingly efficient (maybe because I was registering on what I thought was the last day and there wasn’t much of a crowd). Rather than the standard canvas bag, we were given fluorescent green plastic (?) bags. I have actually wondered whether I hallucinated this, since I threw mine out immediately and have been completely unable to find a picture on one on the internets, but Rex over at Savage Minds has also commented on the bizarre bags (alas, I don’t think they were soy fiber, Rex).

Then there were the conference badges. Not so much badges as they were bibs — a bonus to the messy eaters in our midst! They were bright red (if you are lucky enough to be a AAA member) and were reminiscent of those travel wallets that are designed to fit a passport and shout “I’m a tourist, please harass me!” Too bad I left my fanny-pack at home. Once again, AAA astounds me with its tone-deaf marking of outsiders. Oh, you’re not a member of our club? Then wear this other-colored bib to display your status for all to see! I’ve been to many different societies’ conferences and AAA is the only one where I’ve experienced this practice.

If we’re being perfectly honest here, I’m not big on conference talks. I generally try to minimize the number of attend. Let’s face it, most conference talks are not great and when you have to submit your talk nine months before the conference, freshness of material tends not to be super high. I spend most of my time at conferences meeting with people: planning a paper with co-authors, strategizing with program officers, meeting with editors, catching up with former students, dining and drinking with colleagues I haven’t seen in years. This is the really productive work of an academic conference. Nonetheless, I was curious what AAA had to offer. I found the online program so difficult to use that I gave up on even trying to find talks I wanted to see (this is another topic that Rex takes up hilariously — I couldn’t agree more on his review). This tool was clearly not designed by anyone who actually attends academic conferences. The more I use it to write this piece, the more comically dysfunctional I realize it is. Who thinks it’s a good idea to hide the author names in a search result? See the screenshot below for an example of what gets returned from a search for Anthropology and Environment Society talks:

screenshot of online schedule search

I organized a session for the Evolutionary Anthropology Society entitled, “Evolutionary Anthropological Approaches to Inequality.” It seemed to me that there is a group of human behavioral ecologists out there doing long-term ethnographic work, measuring economic and demographic variables, and thinking hard about how people adapt in a rapidly-changing world, and that these scholars might have some real insights into the mechanisms generating economic inequality. I was right.

One of my goals for this session was to beat the bushes for contributions from scholars other than the usual suspects. Don’t get me wrong; I’m very fond of the usual suspects in EAS, but there is a lot of great work being done that is both relevant to our section’s mission and engages different communities of scholars. I had some success recruiting different people in the initial call for papers. Unfortunately, when these new folks saw how much it costs to present a paper at AAA (the conference is very expensive, particularly when you adjust for the overall quality of the scientific program), they backed out. Fortunately, we had enough people still signed up that we were able to retain our session (apparently, you only need four speakers to stay on the program). When faced with a sparse session, the organizer has a few options: add a discussant, give speakers longer slots, open up a discussion. I decided to opt for yet another strategy. We wildcatted three late-breaking talks by junior researchers. Obviously, these talks didn’t make the program (not sure that’s much of a penalty though, given what a mess the program was), but it still gave the speakers the opportunity to present their research in front of a crowd of at least 50 (we had a great turn-out for the entire session).

The line-up for the session included a number of stars from EAS (well, and me):

  1. Paul Hooper (Emory), “If You Know What Feeds Hierarchy, then You Can Starve It”
  2. Siobhán Mattison (UNM), “Market Integration, Kinship, and Social Inequality Among the Mosuo of Southwest China”
  3. me (Stanford),”State-Dependence, Uncertainty, and the Economic Rationality of Poor People”
  4. Katie Starkweather (MPI), “Subsistence Strategies: Risk, Reward and Gender Roles for the Boat-Dwelling Shodagor of Bangladesh”

We missed Tamas David-Barrett, who had to deal with some emergent business back home. Our late-breaking talks were contributed by Elspeth Ready (Stanford), E’lana Jordan (Stanford), and Dave Nolin (Missouri). All were great. This was E’lana’s debut, as she is just back from the field, and she killed it. Elspeth was, as ever, dazzling in her analytical sophistication and the general bad-assery of her fieldwork.

The other EAS session, “Finding Insights in the Field: Ethnographic Experience and the Scientific Process,” organized by former student and current Omidyar post-doc at SFI, Elly Power, was also terrific. All the talks in this session were very good and the attendance was excellent. Naturally, I was particularly partial to the incredibly sophisticated analysis that Elly presented to close out this excellent session.

This has now happened enough times at AAA that it has tweaked that paranoid part of my brain. Our EAS session was scheduled at the same time as a great-looking session sponsored by Anthropology and the Environment Society called “Emergent Landscapes, Disturbance Ecology, and New Approaches in Ecological Anthropology.” Friends and colleagues involved in this session included Mark Moritz (Ohio State), Steve Lansing (Nanyang Technological University, Singapore), Brian Codding (Utah), Sean Downey (Maryland), and Kathy Galvin (Colorado State), among others. This session would have been of great interest to many in EAS, but, unless you’re Hermione Granger, you can only be in one session at a time. It was particularly frustrating because the editor for the new journal, Nature Human Behavior, also had to choose between sessions. These are constituencies who have natural affinities and we should work on getting them to coordinate somehow, AAA scheduling be damned.

Once again, there was apparently nothing newsworthy at AAA, as a Google news search turns up no hits from the actual meeting. This is a big difference between AAA and other major professional meetings, where new discoveries or novel analyses make their way into different quarters of the news media. The usual defensive response to this critique is that anthropology is more a humanities discipline (which, of course, is itself debatable) and, as such, doesn’t lend itself to “discoveries” or press releases. I don’t buy that. A similar search for the MLA, for example, turns up quite a few stories. I think it’s something about which we should be concerned as a discipline. While I am heartened by some of the work I saw at AAA (or from which I was structurally blocked from seeing but about which I heard in conversations with speakers later that evening), I really wonder about the relevance of our discipline as a whole. In principle, I believe the world really needs anthropology — perhaps now more than ever. But, in practice, I’m not sure what anthropologists are doing is what the world needs.

Among other things, I wonder if we really need to have meetings in convention centers. The public spaces seemed particularly sparse this year and many of the sessions I walked by looked like they had more speakers than audience members. I know it’s hard, but maybe we need to conduct a bit of quality control. Of course, I should be careful what I ask for. Given the fact that EAS is not a powerful section of AAA, we would almost certainly lose, even though our sessions are very well attended. This may sound heretical, but maybe we should collect data on session attendance and factor that into which sessions get included. Surely, the number of people who actually attend a session is a better measure of interest than the number of people who belong to a given section. In my experience, both EAS, BAS, and Anthropology and the Environment would do quite well on that criterion, even if they are relatively small sections.

I will probably keep going to AAA, at least occasionally, not because I think it’s a good conference in general. I will go because there is a core of great young researchers in EAS and I want to continue to support them, even if AAA is, at best, an uneasy home for them.

Winter Anthropology Colloquium, Part 2

We had the second of our speakers in the winter anthropology colloquium Friday. Daniel Nettle came on Friday. Daniel’s talk was co-sponsored by the Institute for Research in the Social Sciences. Daniel is a human behavioral ecologist with extremely broad interests and a penchant for using HBE as a tool for studying social inequality and human health. Somehow, we’d never met before. I’m glad that’s been taken care of now. Of the dozens of things that Daniel could have talked about, he chose to talk about his ethnographic project in Newcastle on Tyne.

Given my interests in demography and epidemiology, I’ve seen lots of talks on social deprivation, inequality, neighborhood effects, etc., but Daniel’s talk showed a refreshing creativity. A large fraction of the data he presented came from deceptively simple ethological methods. I think that there is a lot that both the methods and theory of behavioral ecology and ethology have to offer studies of social inequality and health. Of course, I’m not alone in this belief. Mhairi Gibson (my collaborator in Uganda) and David Lawson (this week’s speaker!) published a terrific  book last year on the application of HBE to applied problems.

Much of the work Daniel’s work in this area is published in open-access journals (e.g., here and here). I’m intrigued by the relatively new journal, PeerJ, where he has published a number of papers now, and am planning to submit something there soon.

The flyer for Daniel’s talk:

Nettle_Talk

Winter Anthropology Colloquium, Part 1

I am organizing the colloquium for the Stanford Anthropology department this winter. I believe it may be the first time that a faculty member for the Ecology and Environment group has organized the colloquium since the Blessed Event that merged departments back in 2008 (though I’m not certain of that). There have been a few scheduling glitches, as it seems winter quarter 2015 has the highest density of talks I’ve yet encountered in 11 years at Stanford, but we’re off to a great start. Our first speaker came all the way from the UK to speak to us about social dilemmas and cooperation. Shakti Lamba is an ESRC Research Fellow and Lecturer in Human Behavioural Ecology in the Centre for Ecology and Conservation at the University of Exeter.

Shakti talked about her very exciting work on behavioral norms. She uses a variety of methods, including ethnography, experimental games, and advanced statistical techniques to understand the nature of variation in cooperative norms within and between populations (see, e.g., papers here or here for examples of her work). I generally have mixed feelings about experimental games, but I think there is a small cadre of anthropologists, including Shakti and Drew Gerkey, among others, who use them as a tool for eliciting much richer behavioral and social observations than do most field researchers (whether or not they use experimental games!). I was impressed by the sophistication of her approach, her keen experimental design, and the excellent population thinking that it entails. However, I was most impressed with her coolness and eloquence under some pretty heated questioning from a number of senior faculty members who simply misunderstand evolutionary process.  Looking forward to seeing more of her work, especially forthcoming longitudinal research with Alex Alvergne, in the future!

Here is the poster for her talk:

Lamba_Talk

Something Newsworthy From the AAAs!

About this time of the year, I generally do a re-cap of the American Anthropological Association’s annual meeting. However, I didn’t attend AAAs this year for the first time in five years, so I don’t have much to report. Anthropologists’ annual awkwardly-timed professional ritual just went down in Washington DC and I thought I would see if anything newsworthy came of it. Doing a Google news search with a variety of permutations of the association name (American Anthropological Association in quotes and not, AAA, etc.) and other keywords (Washington, annual, meeting, 2014, etc.), I managed to find one or two things. As I (and others) have noted before, the AAA meetings don’t attract a lot of press. New discoveries or items of broad public interest are apparently not generally discussed at AAA. This year, the most notable item in a news search is the rejection of a resolution to boycott Israel over what the resolution referred to as “Israel’s ongoing, systematic, and widespread violations of Palestinian academic freedom and human rights.”

One other item popped up which actually resembles something newsworthy on the scholarly front (as opposed to the business of the association).  Kari Lyderson at the Crux writes about a movement to bring anthropological expertise to bear on the ongoing Ebola Virus Disease epidemic in West Africa. Sharon Abramowitz, a terrific medical anthropologist at the University of Florida, has helped to found an initiative called the Ebola Emergency Response Initiative, the aim of which is to provide social and cultural expertise to help with control of the EVD epidemic. This is good news and exactly the sort of thing I would like to see more of at AAA. There are many ways that improved cultural understanding by medical personnel and public health practitioners could help to bring this epidemic under control – a point that anthropologist/human behavioral ecologist Barry Hewlett been making for years now. These are issues we’ve thought about a bit here and that my Ph.D. student Gene Richardson is actively working on in Sierra Leone right now.

Ebola Event at UCI: Planning, Not Panic

I am just back from an event at the University of California, Irvine organized by medical demographer Andrew Noymer. The event drew a big crowd, with probably 500-600 people in attendance.

There were five invited plenary speakers: Michael Buchmeier (UCI) spoke about the virology of Ebola and the Filovriuses more generally. Hearing Mike’s insights on the not one, but two vaccines for Ebola that have been shelved for a decade due to lack of interest was particularly illuminating. George Rutherford (UCSF) talked about the epidemiology of the current EVD epidemic and placed control efforts within the broader context of Global Health Initiatives. This is a guy with a ton of experience in global health and on the ground in Africa and his cool demeanor was calming for the crowd. Victoria Fan (Hawai’i) discussed the economic implications of the epidemic. Spoiler alert: they’re not good. Shruti Gohil (UCI Medical Center) talked about infection control in a hospital setting. Finally, I talked about the disease ecology, broadly construed, of Ebola. Following our talks, we got together as a panel and took questions for the audience.

Given the crazy hysteria surrounding the EVD epidemic and the arrival of a handful of cases in the United States, it was reassuring to participate in a couple hours of such sober, scientifically-informed discussion. Shruti’s insights as chief of infection control at the UCI medical center particularly struck me. She noted that Texas Health Presbyterian Hospital in Dallas, where the first American EVD case (Thomas Duncan) was treated, was clearly completely unprepared to handle an acute EVD case. Despite this, Shruti estimated that the attack rate of health care workers who attended to Duncan was about 4%. Not that horrible for an unprepared hospital. She also noted that no health care workers have become infected in the special units specifically designed to handle infectious diseases like EVD at Emory, Nebraska, and Bethesda. Planning, strict adherence to protocols, and personal protective gear work!

So, let’s summarize a bit about EVD in the US (these are the numbers as best as I can remember them, with citations where I can find them):

Number of cases of evacuated aid workers infected in Africa: 4

Number of deaths of evacuated aid workers infected in Africa: 0

Number of travel-associated cases in US: 4

Number of deaths of travel-associated cases in US: 1

Number of cases of American health care workers: 2

Number of deaths of American health care workers: 0

Note that the one death (Thomas Duncan) might have been prevented if he hadn’t been sent home from the emergency room and gotten so much sicker.

Another interesting point that Shruti made is that none of Duncan’s close personal contacts have contracted EVD and the 21-day window has now passed. The clear implication of all these data is that Ebola is not that infectious. It is controllable if we are prepared and follow protocols.

This gives me hope that we can control the EVD epidemic in West Africa if we were to decide to get serious about its control. But the international community needs to fight this epidemic where it is currently raging. This is clearly in the national interest of the United States and the collective interest of the international community. If we want to remain secure from EVD, we need to stop it where the epidemic continues to grow. World Bank President, and medical anthropologist extraordinaire, Jim Kim pulled out a great analogy in an interview on NPR on 17 October:

It’s like you’re in your room and the house is on fire, and your approach is to put wet towels under the door. That might work for a while, but unless you put the fire out, you’re still in trouble.

Let’s get over our fear, stop politicizing this crisis, stop demonizing the heroes. Let’s roll up our sleeves, get out our checkbooks, and bring a speedy end to this crisis.  Let’s put out the fire.

 

Seriously, People, It's Selection, Not Mutation!

I just read an excellent piece at Slate.com this morning by Benjamin Hale. He notes that the scariest, most insidious thing about Ebola Virus Disease is that the disease capitalizes on intimate contact for transmission. While diseases such as influenza or cholera are transmitted by casual contact, frequently to strangers, via aerosolized droplets (influenza) or fecally contaminated water (cholera). Caretakers, and especially women, are hit hard by EVD. Hale writes,

…the mechanism Ebola exploits is far more insidious. This virus preys on care and love, piggybacking on the deepest, most distinctively human virtues. Affected parties are almost all medical professionals and family members, snared by Ebola while in the business of caring for their fellow humans. More strikingly, 75 percent of Ebola victims are women, people who do much of the care work throughout Africa and the rest of the world. In short, Ebola parasitizes our humanity.

True, and tragic, enough. But this article falls prey to one of my biggest frustrations with the reporting of science, one that I have written about recently in the context of the current EVD epidemic ravaging West Africa.

In the list Hale presents of the major concerns about EVD, he notes: “The threat of mutation,” citing concern that Ebola virus might become airborne in a news report in Nature and the New York Times article that got me so worked up 10 days ago. Earlier this week, there was yet another longish piece in Nature/Scientific American that mentions “mutation” seven times but never once mentions selection. Or in another Nature piece,  UCSF infectious disease physician Charles Chiu is quoted: “The longer we allow the outbreak to continue, the greater the opportunity the virus has to mutate, and it’s possible that it will mutate into a form that would be an even greater threat than it is right now.” True, mutations accumulate over time. Not true, mutation alone will make Ebola virus a greater threat than it is now. That would require selection.

While the idea of airborne transmission of Ebola virus is terrifying, the development of the ability to be transmitted via droplet or aerosol would be an adaptation on the part of the virus. Adaptations arise from the action of selection on the phenotypic variation. Phenotypes with higher fitness come to dominate the population of entities of which they are a part. In the case of a virus such as Ebola virus, this means that the virus must make sufficient copies of itself to ensure transmission to new susceptible hosts before killing the current host or being cleared by the host’s immune system. While efficient transmission of EVD by aerosol or droplet would be horrible, equally horrible would be an adaptation that allowed it to transmit more efficiently from a dead host. It’s not entirely clear how long Ebola virus can persist in its infectious state in the environment. In a study designed to maximize its persistence (indoors, in the dark, under laboratory conditions), Sagripanti and colleagues found that Ebola virus can persist for six days. Under field conditions, it’s probably much shorter, but CDC suggests that 24 hours in a reasonably conservative estimate.

The lack of a strong relationship between host survival and pathogen transmission is why cholera can be so devastatingly pathogenic. The cholera patient can produce 10-20 liters of diarrhea (known as “rice water stools”) per day. These stools contain billions of Vibrio cholerae bacteria, which enter the water supply and can infect other people at a distance well after the original host has died. The breaking of the trade-off between host mortality and the transmissibility of the pathogen means that the natural break on virulence is removed and the case fatality ratio can exceed 50%. That’s high, kind of like the current round of EVD. Imagine if the trade-off between mortality and transmission in EVD were completely broken…

Changes in pathogen life histories like increased (or decreased) virulence or mode of transmission arise because of selection, not mutation, and this selection results from interactions with an environment that we are actively shaping. Sure, mutation matters because it provides raw material upon which selection can act, but the fact remains that we are talking primarily about selection here. Is this pervasive misunderstanding of the mechanisms of life the result of the war of misinformation being waged on science education in the US? I can’t help but think it must at least be a contributor, but if it’s true, it’s pretty depressing because this misunderstanding is finding its way to some of the world’s top news and opinion outlets.

What Dinosaurs Teach Us About Approaching Stanford

My wife, Libra Hilde, and I are resident fellows in a freshman dorm at Stanford. The RF residences are, shall we say, not quite as grand as the masters’ residences at Harvard (which have been know to get named in Top Five Lists of Apartments in Boston), but we fill a similar ceremonial role for our students that the masters at Harvard do. This means giving speeches to parents when students arrive and for important occasions like Parents’ Weekend.

Every year, the house staff (RFs and student staff) pick a theme and then decorate the dorm in anticipation of freshman arrivals. The standard Stanford gag is to pick a theme that somehow plays off the name of the house. These themes can be hilariously tenuous — that’s actually part of the gag — and some house names are easier to work with than others. I’m afraid we’re saddled with a particularly difficult name to play off of. We are Arroyo House. Our themes over the past few years have been: “Where the Wild Things Arroyo” (as in the classic Maurice Sendak book), “ATROYO” (an ancient Greek theme), and “Arroyosemite” (as in the National Park). After a long debate at our staff retreat, we finally decided on this year’s theme of “Dinosarroyo.” Lots of great decorating opportunities, as you can see from this picture of our common room.

Arroyo House LoungeA little game I play with myself in my ceremonial role of Arroyo House Resident Fellow is to welcome the parents with a brief speech on how our house theme relates to their kids’ careers at Stanford and beyond. Now bear in mind, we choose the theme on the basis of (1) how good a pun it makes with our house name (and we don’t have a lot to work with on that front!) and (2) the decoration possibilities it entails. How that theme fits into our larger vision is, frankly, pretty low on the list. This is what makes the game fun! After giving it a bit of thought, it occurred to me that Dinosarroyo actually has a lot to teach us. There are three big themes:

(1) College is about the spirit of discovery. Romantic tales of the expeditions of paleontologists such as Edward Drinker Cope or Roy Chapman Andrews of the American Museum of Natural History have inspired the early careers of countless scientists. Students’ experience at Stanford should inspire them to explore the boundaries of knowledge, whether they are future scientists, educators, lawyers, entrepreneurs, or whatever. Stanford students excel most when they eschew the easy path. This is a research university. Our students should take advantage of this and make new discoveries about the world. Embrace the spirt of discovery embodied by those romantic vertebrate paleontologists.

(2) The Dinosauria first appeared on Earth during the Triassic period and were the dominant form of animal life for over 135 million years. The age of the dinosaurs came to an abrupt end at the Cretaceous-Paleogene Boundary, about 65 million years ago. This 135 million years that dinosaurs dominated is approximately 100 times longer than anything recognizably human has been on the planet. In fact, what appears to us to be a geological ‘instant’ where the dinosaurs went extinct at the K-Pg boundary was, in fact, probably longer than humans have been in existence. That this mighty and diverse lineage of animals managed to die out in the blink of an evolutionary eye suggests to me that we should have some humility about our own dominion. Crucially, at this moment in human history we are faced with many enormous challenges, some of which are potentially existential. We should use the incredible opportunities that are afforded to us by our association with this incredible institution to address these challenges. Our society has given us so much to allow us to be here at this remarkable point in history. Let’s make the most of it!

(3) Those synapsid ancestors of mammals who managed to survive when all the (non-bird) dinosaurs went extinct give us a clue as to what our comparative advantage in this universe is. We are adaptable. We are opportunistic. Most remarkably of all, our particular lineage is blessed with the capacity for planning and foresight. We need to encourage our students to take advantage of the opportunities given them by this university to become adaptable lifelong learners. I can’t predict what the job market will look like in 10 years (and anyone who tells you they can is either fooling themselves or trying to sell you something). What I can say, is that it will be different than it is today. And the job market ten years beyond that will be even more different. This means that learning to be flexible, adaptable, and to never stop learning is probably the greatest ‘skill’ our students can learn.

 

Selection is What Matters

This has to be a quick one, but I wanted to go on the record is noting my frustration at the current concern that Ebola might “mutate” into something far worse, like a pathogen that is efficiently transmitted by aerosol. For example, Michael Osterholm wrote in the New York Times yesterday, “The second possibility is one that virologists are loath to discuss openly but are definitely considering in private: that an Ebola virus could mutate to become transmissible through the air.”  I heard Morning Edition host David Greene ask WHO Director Margaret Chan last week, “Is this virus mutating in a way that could be very dangerous, that could make it spread faster?”

I agree, Ebola Virus becoming more easily transmitted by casual contact would be a ‘nightmare scenario.’ However, what we need to worry about is not mutation per se, but selection! Yes, the virus is mutating. It’s a thing that viruses do. Ebola Virus is a Filovirus. It is composed of a single strand of negative-sense RNA. Like other viruses, and particularly RNA viruses, it is prone to high mutation rates. This is exacerbated by the fact that RNA polymerases lack the ability to correct mistakes. So mutations happen fast and they don’t get cleaned up. Viruses also have very short generation times and can produce prodigious copies of themselves. This means that there is lots of raw material on which selection can act, because variation is the foundation of selection. Add to that heritability, which pretty much goes without saying since we are talking about the raw material of genetic information here, and differential transmission success and voilà, selection!

And virulence certainly responds to selection. There is a large literature on experimental evolution of virulence. See for example the many citations at the linked to Ebert’s (1998) review in Science here. There are lots of different specific factors that can favor the evolution of greater or lesser virulence and this is where theoretical biology can come in and make some sense of things. Steve Frank wrote a terrific review paper in 1996, available on his website, that describes many different models for the evolution of virulence. Two interesting regularities in the the evolution of virulence may be relevant to the current outbreak of EVD in West Africa. The first comes from a model developed by van Baalen & Sabelis (1995). Noting that there is an inherent trade-off between transmissibility of a pathogen and the extent of disease-induced mortality that it causes (a virus that makes more copies of itself is more likely to be transmitted but more viral copies means the host is sicker and might die), they demonstrate that when the relative transmissibility of a pathogen declines, its virulence will increase. They present a marginal value theorem solution for optimal virulence, which we can represent graphically in the figure below. Equilibrium virulence occurs where a line, rooted at the origin, is tangent to the curve relating transmissibility to disease-induced mortality. When the curve  is shifted down, the equilibrium mortality increases. EVD is a zoonosis and it’s reasonable to think that when it makes the episodic jump into human populations, it is leaving the reservoir species the biology of which it is adapted to and entering a novel species to which it is not adapted. Transmission efficiency very plausibly would decrease in such a case and we would expect higher virulence.

Marginal Value Theorem

The second generality that may be of interest for EVD is discussed by Paul Ewald in his book on the evolution of infectious disease and (1998) paper. Ewald notes that when pathogens are released of the constraint between transmissibility and mortality — that is, when being really sick (or even dead) does not necessarily detract from transmission of the pathogen — then virulence can increase largely without bound. Ewald uses the difference in virulence between waterborne  and directly-transmitted pathogens to demonstrate this effect. At first glance, this seems to contradict the van Baalen & Sabelis model, but it doesn’t really. The constraint is represented by the curve in the above figure. When that constraint is released, the downward-sloping curve becomes a straight line (or maybe even an upward-sloping curve) and transmissibility continues to increase with mortality. There is no intermediate optimum, as predicted by the MVT, so virulence increases to the point where host mortality is very high.

A hemorrhagic fever, EVD is highly transmissible in the secretions (i.e., blood, vomit, stool) of infected people. Because these fluids can be voluminous and because so many of the cases in any EVD outbreak are healthcare workers, family members, and attendants to the ill, we might imagine that the constraints between transmissibility and disease-induced mortality on the Ebola Virus could be released, at least early in an outbreak. As behavior changes over the course of an outbreak — both because of public health interventions and other autochthonous adaptations to the disease conditions — these constraints become reinforced and selection for high-virulence strains is reduced.

These are some theoretically-informed speculations about the relevance of selection on virulence in the context of EVD. The reality is that while the theoretical models are often supported by experimental evidence, the devil is always in the details, as noted by Ebert & Bull (2003). One thing is certain, however. We will not make progress in our understanding of this horrifying and rapidly changing epidemic if all we are worried about is the virus mutating.

Selection is overwhelmingly the most powerful force shaping evolution. The selective regimes that pathogens face are affected by the physical and biotic environments in which pathogens are embedded. Critically, they are also shaped by host behavior. In the case of the current West African epidemic of EVD, the host behavior in question is that of many millions of people at risk, their governments, aid organizations, and the global community. People have a enormous potential to shape the selective regime that will, in turn, shape the pathogen that will infect future victims. This is what we need to be worrying about, not whether the virus will mutate. It saddens and frustrates me that we live in a country where evolution is so profoundly misunderstood that even our most esteemed, and otherwise outstanding sources of information and opinion don’t understand the way nature works and the way that human agency can change its workings for our benefit or detriment.

 

 

notes on human ecology, population, and infectious disease