monkey's uncle

I am done with this year’s American Association of Physical Anthropologists annual meeting in Portland. Alas, I am not yet home as I had a scheduling snafu with Alaska Airlines yesterday and there was literally not a single seat on a flight to any airport in the Bay Area. So, I hung out in PDX for the night, where my sister-in-law is finishing up her MD/MPH at OHSU. Staying an extra night allowed me to have dinner at what is probably my favorite pizzeria on the West Coast, Bella Faccia on Alberta Ave in Northeast (Howie’s in Palo Alto is a close second). I also had a lovely breakfast of risotto cakes and poached eggs at La Petite Provence, also on Alberta. All in all, a fantastic couple days’ worth of food.

It was great to get a chance to catch up with old friends and colleagues and meet new ones. This is really what professional meetings are about. I had a chance to spend time with Charles Roseman, Rick Bribiescas, Josh Snodgrass, my EID buddy Nelson Ting, Kirstin Sterner, and Frances White. I also had very nice, if too brief, chats with Connie Mulligan, Lorena Madrigal, Larry Sugiyama, Greg Blomquist, Zarin Machanda, Melissa Emery Thompson, Cheryl Knott, Andy Marshall, and Chris Kuzawa.

I only go to the AAPAs every couple of years. Given the interdisciplinarity of my work and interests, I struggle to find a “home” professional meeting. Sometimes I feel like it’s PAA; sometimes Sunbelt; sometimes AAPA/HBA.  One thing I can say for certain is that it is not AAA, my semi-annual experience in ethnographic surreality. Such a peculiar discipline anthropology is. Part of the reason I don’t go to AAPAs all that often is that I rarely find all that much interesting there. There are a few really fantastic people working in the field, but most of the talks I find stupifyingly boring. I’m just not that interested in teeth. I suppose this is true for any professional meeting, so I shouldn’t be too hard on AAPA — I’m also not especially interested in contraceptive uptake, social media/online networks, or governmentality, apparently the modal topics in my competing meetings. In fact, I was pleasantly surprised by the diversity and quality of talks I saw at AAPA this year.

In my session alone, I saw really terrific and interesting talks by Steve Leigh and Connie Mulligan. Steve spoke on the comparative gut microbiomes of primates and Connie presented early results on the modification of gene expression through methylation of infants born to women who experienced extreme psychosocial and physical trauma in eastern Congo. Really important stuff. It also struck me that you’d probably only see these types of talks at the AAPAs.

There were a lot of young people at this meeting — a greater fraction than I remember from past meetings.  Maybe it was the draw of hipster Portland with its great beer, great food, and general atmosphere of grooviness. Maybe there really are lots and lots of young physical anthropologists being trained these days. I must admit that I had mixed feelings about this thought as I looked out over the vast river of twenty-something faces pouring into the hotel bar Saturday night. On the one hand, it’s great that people are being trained to do good work in physical anthropology. On the other hand, I worry about the ability of our discipline, which shows no signs of stopping with the charade that somehow anthropology is really akin to literary criticism, to absorb this many new Ph.D.s from (one of) the scientific wings of modern anthropology.

Two of the talks immediately before me in my session were, in fact, by young scientists and they were great. Andrew Paquette, from Northern Arizona University, gave a talk on the evolutionary history of Southeast Asian Ovalocytosis (SAO), a twenty-seven base pair deletion in the eleventh exon of the SLC4A1 gene that confers strong protection against infection with Plasmodium falciparum, the most dangerous form of malaria. Turns out this mutation, which has its geographic epicenter in Nusa Tenggara in Indonesia, is surprisingly ancient. Lots more to come from this, I’m sure. Margaux Keller, from Temple, gave a fantastic talk on finding some of the missing heritability in Parkinson’s disease. Missing heritability of complex disease phenotypes is a major topic in genetic epidemiology and Margaux and her colleagues applied Genome-Wide Complex Trait Analysis to eight cohorts of case-control studies of PD. Their results substantially increase (i.e., by a factor of 10!) the fraction of total phenotypic variance in PD explained compared to straight-up genome-wide association studies (GWAS). In addition to the excellent scientific content of her presentation, I was struck by the very nice and original visual aesthetic of her slides.

I spoke on my recent work on the quantitative genetics of life-history traits.  With Statistics grad student Philip Labo, I’ve been doing some pretty serious number-crunching to examine the heritabilities of and (more interestingly) genetic correlations between human life-history characters. Good results that should be seeing some more light soon (including at PAA next month!).

Tom Scocca has wrote a brilliant essay in Slate today on the absurdities of Microsoft Word being the standard text processing tool in the age of digital publishing. I struggle to get students doing statistical and demographic analysis in R to not use Word because of all the unwanted junk it brings to the most trivial text-processing task. Using the word2cleanhtml website, Scocca shows how a two-word text chunk written in Word contains the equivalent of eight pages of unnecessary hidden text!

I encounter all the nonsense associated with the annoying default “annoying typographical flourishes” that Scocca discusses in my role as associate editor of a couple of journals and a regular reviewer for NSF. Both of these roles make extensive use of web-based platforms for managing workflows associated with writing-intensive tasks (ScholarOne for editing and Fastlane for NSF) and both snarf on the typographical annoyances Scocca enumerates (“smart” quotes, automatic em-dashes, etc.). When you do an NSF panel, you receive a briefing explaining that if you are going to write your panel summaries in Word, you need to turn off smart quotes and avoid other things that will lead to nonsense in the plain-text formatted fields of Fastlane. Of course, no one does this.

Don’t get me started on track changes…

I do the great majority of my own writing in a plain text-processor. My personal favorite is Aquamacs, a Mac-native variation on GNU Emacs. Emacs is definitely not for everyone, but there are lots of other possibilities. Scocca writes that he has turned to TextEdit, which is another Mac-native, but there are plenty of other options that run on different systems. Here is a list of possibilities.

It will be interesting to see how online collaborative tools such as Google Docs change the way people do text processing.  I find that more of my students do their work in Google Docs. It’s certainly not a majority yet but the fraction is growing rapidly each year. As Scocca notes, Google Docs provides a much more sane alternative to track changes, among other things.

Microsoft clearly needs to get serious and do a bit of innovation here if they want to stay in this particular game. I, for one, will not miss MS Word if it should go the way of WordStar.

I recently read a story in the Los Angeles Times about a team of psychologists at UC Berkeley who showed, in a series of experimental and naturalistic studies, that wealthy individuals are more likely to cheat or violate social norms about fairness. The Story in the Times referred to the paper by Piff et al. in the 27 February edition of PNAS.  Here is the abstract of this paper:

Seven studies using experimental and naturalistic methods reveal that upper-class individuals behave more unethically than lower-class individuals. In studies 1 and 2, upper-class individuals were more likely to break the law while driving, relative to lower-class individuals. In follow-up laboratory studies, upper-class individuals were more likely to exhibit unethical decision-making tendencies (study 3), take valued goods from others (study 4), lie in a negotiation (study 5), cheat to increase their chances of winning a prize (study 6), and endorse unethical behavior at work (study 7) than were lower-class individuals. Mediator and moderator data demonstrated that upper-class individuals’ unethical tendencies are accounted for, in part, by their more favorable attitudes toward greed.

This study was apparently motivated by observations that people in expensive luxury cars are more likely to bolt ahead of their turn at four-way stop intersections in the San Francisco Bay Area, a daily experience for anyone driving in Palo Alto! It’s terrific that these authors actually took the trouble to systematize their casual observations of driving behavior and make an interesting and compelling scientific statement.

On Friday, I made my own observations about class, cheating, and the violation of norms as I flew down to LAX to attend Sunbelt XXXII (the annual conference for the International Network for Social Network Analysis). Of late, I’ve racked up a lot of miles on United and, as a result, occasionally get upgraded to first class or business class seating. My trip Friday was one of those occasions. As I sat in the (relatively) comfy leather seat of the first-class cabin reading Jeremy Boissevain’s rather appropriate (1974) book Friends of Friends: Networks, Manipulators, and Coalitions, I noticed that nearly everyone around me was busily chatting away or otherwise fiddling around with their smart phones. When the cabin door finally closed and the announcement was made requesting that phones be switched off, none of the people in my neighborhood did so. They put their phones down or in their shirt pockets and watched the flight attendants.  When the flight attendants passed through the cabin and were occupied with other business, out came the smart phones again. The one gentleman across the aisle from me looked like a school kid writing a note in class or something. He kept a wary half-eye out for the flight attendants and looked extremely guilty about his actions, but he nonetheless kept doing his, no doubt, extremely important business.  The man on the phone in the row ahead of me was a little more shameless. He seemed completely unconcerned that he might get busted. The woman in the row ahead of me and across the aisle moved her phone so that it was partially hidden by the arm-rest of her seat as she continued to scroll through her very, very important email. Of the six people I could easily see in my neighborhood, fully half of them continued to use their phones right into taxi and take-off.  Based on their attempts at concealment, at least two of them knew what they were doing was wrong. Now, any regular traveler has seen people using their phones on the plane after they are supposed to. However, I had never seen this sort of density of norm violation on a single flight before.

Of course, this is an anecdote but the study by Piff et al. (2012) shows how anecdotes about social behavior can go on to be systematized into interesting scientific studies.

When I was in Uganda last month, I was talking with collaborators, field assistants, villagers, taxi drivers, bartenders – pretty much anyone who would listen – about social networks, I was struck by what a sophisticated understanding of social networks my average interlocutor had.  As part of our project examining the risk of zoonotic disease spillover in rural Uganda, we are gathering data on individual people’s personal networks. We are interested in contact networks, for sure, but we are also examining people’s social capital – the resources to which an individual has access for instrumental action that are embedded in his or her social network. There are generally two classes of definitions of social capital used in the literature. The first, made famous by Robert Putnam‘s book, Bowling Alone, is really a measure of community solidarity. How cohesive are communities and how does this contribute to individuals’ and communities’ welfare?  The definition I typically employ is attributable to Bourdieau and a host of other scholars, especially Nan Lin. This definition emphasizes both the networked nature of social capital and the instrumentality of it.

The reasoning behind doing a social capital inventory in conjunction with our study of zoonotic disease spillover risk is to have a thorough description of the “state” of individuals. Social surveys typically measure income, household wealth, land holdings, etc. One measures such things in a social survey because one is interested in the economic state of the individual or household in which she is embedded. Social capital is a measure of economic – and social – well-being for people where many of the resources that they need to succeed, or even just get by, are not specifically located in the household or with the individual. We suspect that people in rural Uganda will vary in the amount of social capital they have and that this may be a major axess of vulnerability.

So, there I am, talking to anyone who would listen about the best way to gather information on personal social networks and it turns out that everyone I spoke with was amazingly familiar with the whole concept of social networks. The catch is, the networks with which they are familiar are a special type of networks – sexual networks. When I asked how everyone seemed to know so much about sexual networks, they pointed me to a public-service advertising campaign for which the tag line is “get off the sexual network.” Despite the Central African origin of HIV-1, Uganda was an early center for the epidemic. However, as noted by Stoneburner and Lowbeer, in their important 2004 paper, Uganda experienced substantial – and early – decline in HIV-1 incidence because of health communication through social networks. They write:

The response in Uganda appears to be distinctively associated with communication about acquired immunodeficiency syndrome (AIDS) through social networks. Despite substantial condom use and promotion of biomedical approaches, other African countries have shown neither similar behavioral responses nor HIV prevalence declines of the same scale. The Ugandan success is equivalent to a vaccine of 80% effectiveness. (Stoneburner & Lowbeer 2004)

I definitely need to check out the current state of the art to see if other countries in Sub-Saharan Africa have now experienced similar public health gains as a result of network-oriented interventions.

Based on my rather unsystematic sample, I’d say that this campaign has really worked raise people’s understanding of relational interconnectedness.  I was not able to get a picture of the huge billboards on the Kampala-Entebbe Highway (because it was always dark when I drove by them) but the TV ad is available on youtube. On the one hand, this is really great (both for the obvious public health reasons and because people seem to have a good understanding of webs of social relations). On the other hand, it will probably mean we will need to work hard to clarify what types of networks we mean when we gather our network data.

Well, it certainly has been a while since I’ve written anything here. Life has gotten busy with new projects, new responsibilities, etc. Yesterday, I participated in a workshop on campus sponsored by the Woods Institute for the Environment, the Young Environmental Scholars Conference. I was asked to stand-in for a faculty member who had to cancel at the last minute. I threw together some rather hastily-written notes and figured I’d share them here (especially since I spoke quite a bit of the importance for public communication!).

The theme of the conference was “Environmental Policy, Behavior, and Norms” and we were asked to answer three questions: (1) What does doing normative research mean to you? (2) How do your own norms and values influence your research? (3) What room and role do you see for normative research in your field? So, in order, here are my answers.

What does doing normative research mean to you?

I actually don’t particularly like the term “normative research” because it sounds a little too much like imposing one’s values on other people. I am skeptical of the imposition of norms that have more to do with (often unrecognized) ideology and less about empirical truth – an idea that was later reinforced by a terrific concluding talk by Debra Satz. If I can define “normative” to mean with the intent to improve people’s lives, then OK.  Otherwise, I prefer to do “positive” research.

For me, normative research is about doing good science. As a biosocial scientist with broad interests, I wear a lot of hats. I have always been interested in questions about the natural world, and (deep) human history in particular. However, I find that the types of questions that really hold my interest these days are more and more engaged in the substantial challenges we face in the world with inequality and sustainability. In keeping with my deep pragmatist sympathies, I increasingly identify with Charles Sanders Pierce‘s idea that given the “great ocean of truth” that can potentially be uncovered by science, there is a moral burden to do things that have social value. (As an aside, I think that there is social value in understanding the natural world, so I don’t mean to imply a crude instrumentalism here.) In effect, there is a lot of cool science to be done; one may as well do something of relevance.  I personally have little patience for people who pursue racist or otherwise socially divisive agendas and cloak their work in a veil of  free scientific inquiry.  This said, I worry when advocacy interferes with intellectual fairness or an unwillingness to accept that one’s position is not actually true.

I think that we are fooling ourselves if we believe that our norms somehow don’t have an effect on our research.  Recognizing what these norms that shape your research – whether implicitly or explicitly – helps you manage your bias. Yes, I said manage. I’m not sure we can ever completely eliminate it. I see this as more of a management of a necessary trade-off, drawing an analogy between the practice of science and statistics, between bias and variance. The more biased one is, the less variance there is in the outcome of one’s investigation. The less bias, the greater the likelihood that results will differ from one’s expectations (or wishes). Recognizing how norms shape our research also deals with that murky area of pre-science: where do our ideas for what to study come from?

How do your own norms and values influence your research?

Some of the the norms that shape my own research and teaching include:

transparency: science works best when it is open. This places a premium on sharing data, methods, and communicating results in a manner that maximizes access to information. As a simple example, this norm shapes my belief that we should not train students from poor countries in the use of proprietary software (and other technologies) that they won’t be able to afford when they return to their home countries when there are free or otherwise open-source alternatives.

fairness: this naturally includes a sense of social justice or people playing on an equal playing field, but it also includes fairness to different ideas, alternative hypotheses, the possibility that one is wrong. This type of fairness is essential for one’s credibility as a public intellectual in science (particularly supporting policy), as noted eloquently in this interview with Dick Lewontin.

respect for people’s ultimate rationality: Trying to understand the social, ecological, and economic context of people’s decision-making, even if it violates our own normative – particularly market-based economic – expectations.

flexibility: solving real problems means that we need to be flexible in our approach, willing to go where the solutions lead us, learning new tools and collaborating. Flexibility also means a willingness to give up on a research program that is doing harm.

good-faith communication: I believe that there is no room for obscurantism in the academy of the 21st century. This includes public communication. There are, of course, complexities here with regard to the professional development of young scholars.  One of the key trade-offs for young scholars is the need for professional advancement (which comes from academic production) and activism, policy, and public communication. Within the elite universities, the reality is that neither public communication nor activism count much for tenure. However, as Jon Krosnick noted, tenure is a remarkable privilege and, while it may seem impossibly far away for a student just finishing a Ph.D., it’s not really. Once you prove that you have the requisite disciplinary chops, you have plenty of time to to use tenure for what it is designed for (i.e., protecting intellectual freedom) and engaging in critical public debate and communication.

humility: solving problems (in science and society) means caring more about the answer to a problem than one’s own pet theory. Humility is intimately related to respect for others’ rationality.  It also means recognizing the inherently collaborative nature of contemporary science: giving credit where it is due, seeking help when one is in over one’s head, etc. John DeGioia, President of Georgetown University, quoted St. Augustine in his letter of support for Georgetown Law Student, Sandra Fluke against the crude attacks by radio personality Rush Limbaugh and I think those words are quite applicable here as well.  Augustine implored his interlocutors to “lay aside arrogance” and to “let neither of us assert that he has found the truth; let us seek it as if it were unknown to both.” This is not a bad description of the way that science really should work.

What room and role do you see for normative research in your field?

I believe that there is actually an enormous amount of room for normative research, if by “normative research,” we mean research that has the potential to have a positive effect on people’s lives. If instead we mean imposing values on people, then I am less sure of its role.

Anthropology is often criticized from outside the field, and to a lesser extent, from within it for being overly politicized. You can see this in Nicholas Wade’s critical pieces in the New York Times Science Times section following the American Anthropological Association’s executive committee excising of the word “science” from the field’s long-range planning document. Wade writes,

The decision [to remove the word 'science' from the long-range planning document] has reopened a long-simmering tension between researchers in science-based anthropological disciplines — including archaeologists, physical anthropologists and some cultural anthropologists — and members of the profession who study race, ethnicity and gender and see themselves as advocates for native peoples or human rights.

This is a common sentiment. And it is a complete misunderstanding. It suggests that scientists can’t be advocates for native peoples or human rights.  It also suggests that one can’t study race, ethnicity, or gender from a scientific perspective.  Both these ideas are complete nonsense.  For all the leftist rhetoric, I am not impressed with the actual political practice of what I see in contemporary anthropology. There is plenty of posturing about power asymmetries and identity politics but it is always done in such a mind-numbingly opaque language and with no apparent practical tie-in to policies that make people’s lives better. And, of course, there is the outright disdain for “applied” work one sees in elite anthropology departments.

Writing specifically about Foucault, Chomsky captured my take on this whole mode of intellectual production:

The only way to understand [the mode of scholarship] is if you are a graduate student or you are attending a university and have been trained in this particular style of discourse. That’s a way of guaranteeing…that intellectuals will have power, prestige and influence. If something can be said simply, say it simply, so that the carpenter next door can understand you. Anything that is at all well understood about human affairs is pretty simple.

Ultimately, the simple truths about human affairs that I find anyone can relate to are subsistence, health, and the well-being of one’s children. These are the themes at the core of my own research and I hope that the work I do ultimately can effect some good in these areas.

I am thrilled to report that our latest EID project proposal, Biological and Human Dimensions of Primate Retroviral Transmission, has now been funded (by NIAID nonetheless!).  I will briefly describe the project here and then shamelessly tack on the full text of our advertisement for a post-doc to work as the project manager with Tony Goldberg, PI for this grant, in the College of Veterinary Medicine, University of Wisconsin, Madison.  This project will complement the ongoing work of the Kibale EcoHealth Project. The research team includes: Tony, Colin Chapman (McGill), Bill Switzer (CDC), Nelson Ting (Iowa), Mhairi Gibson (Bristol), Simon Frost (Cambridge), Jennifer Mason (Manchester), and me. This is a pretty great line-up of interdisciplinary scholars and I am honored to be included in the list.

Biological and Human Dimensions of Primate Retroviral Transmission

One of the great enduring mysteries in disease ecology is the timing of the AIDS pandemic. AIDS emerged as a clinical entity in the late 1970s, but HIV-1, the retrovirus that causes pandemic AIDS, entered the human population from wild primates many decades earlier, probably near the turn of the 20th century. Where was HIV during this long interval? We propose a novel ecological model for the delayed emergence of AIDS. Conceptually, in a metapopulation consisting of multiple, loosely interconnected sub-populations, a pathogen could persist at low levels indefinitely through a dynamic balance between localized transmission, localized extinction, and long-distance migration between sub-populations. This situation might accurately describe a network of villages in which population sizes are small and rates of migration are low, as would have been the case in Sub-Saharan Africa over a century ago.

We will test our model in a highly relevant non-human primate system. In 2009, we documented three simian retroviruses co-circulating in a metapopulation of wild red colobus monkeys (Procolobus rufomitratus) in Kibale National Park, Uganda, where we have conducted research for over two decades. We will collect detailed data on social interactions, demography, health, and infection from animals in a core social group.

We will also study a series of 20 red colobus sub-populations, each inhabiting a separate, isolated forest fragment. We will determine the historical connectivity of these sub-populations using a time series of remotely sensed images of forest cover going back to 1955, as well as using population genetic analyses of hypervariable nuclear DNA markers. We will assess the infection status of each animal over time and use viral molecular data to reconstruct transmission pathways.

Our transmission models will define the necessary conditions for a retrovirus to persist, but they will not be sufficient to explain why a retrovirus might emerge. This is because human social factors ultimately create the conditions that allow zoonotic diseases to be transmitted from animal reservoirs and to spread. We will therefore conduct an integrated analysis of the root eco-social drivers of human-primate contact and zoonotic transmission in this system. We will study social networks to understand how social resources structure key activities relevant to human-primate contact and zoonotic transmission risk, and we will explore knowledge, beliefs, and perceptions of human-primate contact and disease transmission for a broad sample of the population. We will reconcile perceived risk with actual risk through a linked human health survey and diagnostic testing for zoonotic primate retroviruses.

The ultimate product of our research will a data-driven set of transmission models to explain the long-term persistence of retroviruses within a metapopulation of hosts, as well as a linked analysis of how human social factors contribute to zoonotic infection risk in a relevant Sub-Saharan African population. Our study will elucidate not only the origins of HIV/AIDS, but also how early-stage zoonoses in general progress from “smoldering” subclinical infections to full-fledged pandemics.

Post Doctoral Opportunity

The Goldberg Lab at the University of Wisconsin-Madison invites applications for a post-doctoral researcher to study human social drivers of zoonotic disease in Sub-Saharan Africa.   The post-doc will be an integral member of a new, international, NIH-funded project focused on the biological and human dimensions of primate infectious disease transmission in Uganda, including social drivers of human-primate contact and zoonotic transmission.  This is a unique opportunity for a post-doctoral scholar with training in the social sciences to study human-wildlife conflict/contact and health and disease in a highly relevant ecological setting.  The following criteria apply.

1. Candidates must have completed or be near to completing a PhD in the social sciences, in a discipline such as anthropology, geography, sociology, behavioral epidemiology, or a relevant discipline within the public health fields.
2. Candidates must have a demonstrated interest in health and infectious disease.
3. Candidates must have prior field experience in Sub-Saharan Africa.
4. Candidates must be willing to relocate to Madison, Wisconsin for three years.
5. Candidates must be willing to spend substantial time abroad, including in Sub-Saharan Africa and at partner institutions in the United Kingdom.
6. Candidates must have experience with collection and analysis of both quantitative and qualitative data.  Familiarity with methods such as social network analysis, GIS, participatory methods, and survey design would be advantageous.

The successful candidate will help lead a dynamic international team of students and other post-docs in a multi-institutional, multidisciplinary project.  Duties involve a flexible combination of fieldwork, analyses, and project coordination, in addition to helping to mentor students from North America, Europe, and Africa.  The successful applicant will be expected to explore new research directions of her/his choosing, assisted by a strong team of collaborators.

University of Wisconsin-Madison is a top-notch institution for research and training in the social and health sciences.  Madison, WI, is a vibrant city with outstanding culture and exceptional opportunities for outdoor recreation.

Applicants should send a current CV, a statement of research interests and qualifications (be sure to address the six criteria above), and a list of three people (names, addresses, e-mails) who can serve as references.

Materials and inquiries should be sent to Dr. Tony L. Goldberg (tgoldberg@vetmed.wisc.edu).  Application materials must be received by September 12, 2011 for full consideration; the position is available starting immediately and requires a three-year commitment.

I am saddened and sickened to learn of the horrific events in Norway today. As I write this, the news is that a total of 80 have died, 7 in the bombing in Oslo and the rest, presumably, at the youth camp in Utoya Island. This is an unimaginable tragedy for the parents of these children and would be wherever such an event occurred.  The impact on aggregate mortality  just happens to be particularly acutely noticeable in a low-mortality country such as Norway.  I look at Norwegian mortality data quite a bit because I use mortality change in Norway as an example in at least two classes I teach. To give a sense of what an enormous impact 80 violent deaths have on the overall mortality of a relatively small, and very low-mortality country like Norway, I plotted the number of deaths by age on semi-logarithmic axes for the latest year for which we have data (2009). I then added the 73 deaths (in red), assuming for simplicity that they all fell on 16 year-olds (since it was a youth camp).  While clearly not true, this allows us to compare the scale of this mass murder with the pace of death in Norway as a whole.

It is plain to see that, beyond the clear impact such an event has on the families directly effected, this senseless act has a substantial effect on the aggregate pattern of mortality for the entire country of Norway.

Expert wrangler of predicaments Phillip Mendonça-Vieira has put together a very cool time-lapse movie from about 12,000 screenshots of the front page of the nytimes.com.  The movie is interesting to watch in a Koyaanisqatsi kind of way, but what I find most poignant is his commentary that accompanies the movie. Mendonça-Vieira writes,

Having worked with and developed on a number of content management systems I can tell you that as a rule of thumb no one is storing their frontpage layout data. It’s all gone, and once newspapers shutter their physical distribution operations I get this feeling that we’re no longer going to have a comprehensive archive of how our news-sources of note looked on a daily basis. Archive.org comes close, but there are too many gaps to my liking.

This, in my humble opinion, is a tragedy because in many ways our frontpages are summaries of our perspectives and our preconceptions. They store what we thought was important, in a way that is easy and quick to parse and extremely valuable for any future generations wishing to study our time period.

This really resonated with me.  Some time back, we wrote a paper that garnered quite a lot of media coverage. Indeed, we even got the ‘front page’ of the nytimes.com, if only fleetingly. I am very glad that I had the presence of mind to save that screen shot as a pdf so I would be able to preserve this 15 minutes of fame for posterity. If they had been available, I would have bought lots of paper copies.  However, what I am left with is this:

This really is a shame and clearly represents a serious challenge for the historians of tomorrow and the archivists of today.

The FAO Food Price Index (FPI) remains at near record-highs, and this at a time when record droughts and calamitous famine threaten the Horn of Africa. Using the latest data from the FAO FPI page, I plot here the FPI time series from 1990-2011.

World food prices are high and have remained so since the beginning of this year, though there have been some pretty dramatic swings between 2008 and now.  There is some argument that the real problem for poverty alleviation is actually price volatility and not high prices per se.  However, a recent paper in Foreign Affairs by Barrett and Bellemare argues that the problem for the world’s poor is really high prices (a more complete working paper can be found here). I find their arguments quite persuasive. Among these, the authors wryly note “Perhaps not coincidentally, [commentators' and politicians'] emphasis on tempering price volatility favors the same large farmers who already enjoy tremendous financial support from G-20 governments.”

It was a conceptually dense week in class.  The first part of the week I spent talking about topics such as ecological complexity, vulnerability, adaptation, and resilience. One of the key take-home messages of this material is that uncertainty is ubiquitous in complex ecological systems.  Now, while systemic uncertainty does not mean that the world is unpatterned or erratic, it does mean that people are never sure what their foraging returns will be or whether they will come down with the flu next week or whether their neighbor will support them or turn against them in a local political fight. Because uncertainty is so ubiquitous, I see it as especially important for understanding human evolution and the capacity for adaptation. In fact, I think it’s so important a topic that I’m writing a book about it.  More on that later…

First, it’s important to distinguish two related concepts.  Uncertainty  simply means that you don’t know the outcome of a process with 100% certainty.  Outcomes are probabilistic.  Risk, on the other hand, combines both the likelihood of a negative outcome and the outcome’s severity. There could be a mildly negative outcome that has a very high probability of occurring and we would probably think that it was less risky than a more severe outcome that happened with lower probability. When a forager leaves camp for a hunt, he does not know what return he will get.  10,000 kcal? 5,000 kcal? 0 kcal? This is uncertainty.  If the hunter’s children are starving and might die if he doesn’t return with food, the outcome of returning with 0 kcal worth of food is risky as well.

Human behavioral ecology has a number of elements that distinguish it as an approach to studying human ecology and decision-making.  These features have been discussed extensively by Bruce Winterhalder and Eric Smith (1992, 2000), among others.  Included among these are: (1) the logic of natural selection, (2) hypothetico-deductive framework, (3) a piecemeal approach to understanding human behavior, (4) focus on simple (strategic) models, (5) emphasis on behavioral strategies, (6) methodological individualism.  Some others that I would add include: (7) ethological (i.e., naturalistic) data collection, (8) rich ethnographic context, (9) a focus on adaptation and behavioral flexibility in contrast to typology and progressivism.  The hypothetico-deductive framework and use of simple models (along with the logic of selection) jointly accounts for the frequent use of optimality models in behavioral ecology. Not to overdo it with the laundry lists, but optimality models also all share some common features.  These include: (1) the definition of an actor, (2) a currency and an objective function (i.e., the thing that is maximized), (3) a strategy set or set of alternative actions, and (4) a set of constraints.

For concreteness’ sake, I will focus on foraging in this discussion, though the points apply to other types of problems. When behavioral ecologists attempt to understand foraging decisions, the currency they overwhelmingly favor is the rate of energy gain. There are plenty of good reasons for this.  Check out Stephens and Krebs (1986) if you are interested. The point that I want to make here is that, ultimately, it’s not the energy itself that matters for fitness.  Rather it is what you do with it. How does a successful foraging bout increase your marginal survival probability or fertility rate? This doesn’t sound like such a big issue but it has important implications. In particular, fitness (or utility) is a function of energy return.  This means that in a variable environment, it matters how we average.  Different averages can give different answers. For example, what is the average of the square root of 10 and 2? There are two ways to do this: (1) average the two values and take the square root (i.e., take the function of the mean), and (2) take the square roots and average (i.e., take the mean of the function). The first of these is \(\sqrt{6}=2.45\). The second is \((\sqrt{10} + \sqrt{2})/2=2.29\).  The function of the mean is greater than the mean of the function.  This is a result of Jensen’s inequality. The square root function is concave — it has a negative second derivative. This means that while \(\sqrt{x}\) gets bigger as \(x\) gets bigger (its first derivative is positive), the increase is incrementally smaller as \(x\) gets larger. This is commonly known as diminishing marginal utility.

Lots of things naturally show diminishing marginal gains.  Imagine foraging for berries in a blueberry bush when you’re really hungry.  When you arrive at the bush (i.e., ‘the patch’), your rate of energy gain is very high. You’re gobbling berries about as fast as you can move your hands from the bush to your mouth. But after you’ve been there a while, your rate of consumption starts to slow down.  You’re depleting the bush.  It takes longer to pick the berries because you have to reach into the interior of the bush or go around the other side or get down on the ground to get the low-hanging berries.

Chances are, there’s going to come a point where you don’t think it’s worth the effort any more.  Maybe it’s time to find another bush; maybe you’ve got other important things to do that are incompatible with berry-picking. In his classic paper, Ric Charnov derived the conditions under which a rate-maximizing berry-picker should move on, the so-called ‘marginal value theorem’ (abandon the patch when the marginal rate of energy gain equals the mean rate for the environment). There are a number of similar marginal value solutions in ecology and evolutionary biology (they all arise from maximizing some rate or another). Two other examples: Parker derived an marginal value solution for the optimal time that a male dung fly should copulate (can’t make this stuff up). van Baalen and Sabelis derived the optimal virulence for a pathogen when the conditional probability of transmission and the contact rate between infectious and susceptible hosts trade off.

So, what does all this have to do with risk? In a word, everything.

Consider a utility curve with diminishing marginal returns.  Suppose you are at the mean, indicated by \(\bar{x}\). Now you take a gamble.  If you’re successful, you move to \(x_1\) and its associated utility.  However, if you fail, you move down to \(x_0\) and its associated utility.  These two outcomes are equidistant from the mean. Because the curve is concave, the gain in utility that you get moving from \(\bar{x}\) to \(x_1\) is much smaller than the loss you incur moving from \(\bar{x}\) to \(x_0\).  The downside risk is much bigger than the upside gain.  This is illustrated in the following figure:

When returns are variable and utility/fitness is a function of returns, we can use expected utility as a tool for understanding optimal decisions. The idea goes back to von Neumann and Morgenstern, the fathers of game theory. Expected utility has received some attention in behavioral ecology, though not as much as it deserves.  Stephens and Krebs (1986) discuss it in their definitive book on foraging theory.  Bruce Winterhalder, Flora Lu, and Bram Tucker (1999) have discussed expected utility in analyzing human foraging decisions and Bruce has also written with Paul Leslie (2002; Leslie & Winterhalder 2002) on the topic with regard to fertility decisions.  Expected utility encapsulates the very sensible idea that when faced with a choice between two options that have uncertain outcomes, choose the one with the higher average payoff. The basic idea is that the world presents variable pay-offs. Each pay-off has a utility associated with it. The best decision is the one that has the highest overall expected, or average, utility associated with it. Consider a forager deciding what type of hunt to undertake. He can go for big game but there is only a 10% chance of success. When he succeeds, he gets 10,000 kcal of energy. When he fails, he can almost always find something else on the way back home to bring to camp. 90% of the time, he will bring back 1,000 kcal.  The other option is to go for small game, which is generally much more certain endeavor. 90% of the time, he will net 2,000 units of energy.  Such small game is remarkably uniform in its payoff but sometimes (10%) the forager will get lucky and receive 3,000 kcal. We calculate the expected utility by summing the products of the probabilities and the rewards, assuming for simplicity in this case that the utility is simply the energy value (if we didn’t make this assumption, we would calculate the utilities associated with the returns first before averaging).

Big Game: 0.1*10000 + 0.9*1000 = 1900

Small Game: 0.9*2000 + 0.1*3000 = 2100

Small game is preferred because it has higher expected utility.

We can do a bit of analysis on our utility curve and show something very important about risk and expected utility. I’ll spare the mathematical details, but we can expand our utility function around the mean return using a Taylor series and then calculate expectations (i.e., average) on both sides.  The resulting expression encapsulates a lot of the theory of risk management. Let \(w(x)\) indicate the utility associated with return \(x\) (where I follow the population genetics convention that fitness is given by a w).

\[ \overline{w(x)} = w(\bar{x}) + \frac{1}{2} w \mathrm{Var}(x). \]

Mean fitness is equal to the fitness of the mean payoff plus a term that includes the variance in \(x\) and the second derivative of the utility function.  When there is diminishing marginal utility, this will be negative.  Therefore, variance will reduce mean fitness below the fitness of the mean. When there is diminishing marginal utility, variance is bad. How bad is determined both by the magnitude of the variance but also by how curved the utility curve is.  If there is no curve, utility is a straight line and \(w=0\).  In that case, variance doesn’t matter.

So variance is bad for fitness.  And variance can get big. One can imagine it being quite sensible to sacrifice some mean return in exchange for a reduction in variance if this reduction outweighed the premium paid from the mean. This is exactly what we do when we purchase insurance or when a farmer sells grain futures.  This is also something that animals with parental care do.  Rather than spewing out millions of gametes in the hope that it will get lucky (e.g., like a sea urchin), animals with parental care use the energy they could spend on lots more gametes and reinvest in ensuring the survival of their offspring. This is probably also why hunter-gatherer women target reliable resources that generally have a lower mean return than other available, but risky, items.

It turns out that humans have all sorts of ways of dealing with risk, some of them embodied in our very biology.  I’m going to come up short in enumerating these because this is the central argument of my book manuscript and I don’t want to give it away (yet)! I hope to blog here in the near future about three papers that I have nearly completed that deal with risk management and the evolution of social systems, reproductive decision-making in an historical population, and foraging decisions by contemporary hunter-gatherers.  When they come out, my blog will be the first to know!

References

Charnov, E. L. 1976. Optimal foraging: The marginal value theorem. Theoretical Population Biology. 9:129-136.

Leslie, P., and B. Winterhalder. 2002. Demographic consequences of unpredictability in fertility outcomes. American Journal of Human Biology. 14 (2):168-183.

Parker, G. A., and R. A. Stuart. 1976. Animal behavior as a strategy optimizer: evolution of resource assessment strategies and optimal emigration thresholds. American Naturalist. 110 (1055-1076).

Stephens, D. W., and J. R. Krebs. 1986. Foraging theory. Princeton: Princeton University Press.

van Baalen, M., and M. W. Sabelis. 1995. The dynamics of multiple infection and the evolution of virulence. American Naturalist. 146 (6):881-910.

Winterhalder, B., and P. Leslie. 2002. Risk-sensitive fertility:The variance compensation hypothesis. Evolution and Human Behavior. 23:59-82.

Winterhalder, B., F. Lu, and B. Tucker. 1999. Risk-sensitive adaptive tactics: Models and evidence from subsistence studies in biology and anthropology. Journal of Archaeological Research. 7 (4):301-348.

Winterhalder, B., and E. A. Smith. 2000. Analyzing adaptive strategies: Human behavioral ecology at twenty-five. Evolutionary Anthropology. 9 (2):51-72.