Research Opportunities

Area 1 Projects

Capuchin Monkey Phylogeography and Cultural Ecology (Jessica Lynch Alfaro & Michael Alfaro) This group is studying phylogenetic and phylogeographic relationships among capuchin monkeys, examining both broad-scale and local patterns of cultural and behavioral evolution. Using a molecular phylogeny as a framework, they are testing whether cultural innovations influenced dispersal patterns and behavioral or morphological diversification. On a local level, in Costa Rica, they are examining population genetics, dispersal patterns and behavioral differences across habitat types in capuchin monkeys. Through a collaboration with the U of Costa Rica’s Biology Department, IPEM Fellows will have the opportunity to gain fieldwork experience studying primates in diverse habitats such as mangroves, wet and dry rainforests, and montane forests in the Central Pacific of Costa Rica. There will also be the possibility for studying human impact on Costa Rican eco-systems and primate ecology, and the University of Costa Rica can offer Fellows laboratory training in microbiology, parasitology, and genetics if desirable for their research.

Model Averaging and Model Choice in Phylogenetics (Michael Alfaro) Phylogenetic analysts try to find genealogical relationships of organisms and in so doing they make strong but testable assumptions about how molecular evolution occurs. Phylogenetic analysis requires first choosing a model of molecular evolution (usually from a small “standard set”) and then finding the best phylogenetic tree describing the relationships among the organisms. Hence, the tree (i.e., one’s conclusion) is model-dependent. In this project we are greatly expanding the set of candidate models and devising “automated” ways to simultaneously search for the best model of molecular evolution and the best phylogeny. We use a Markov-chain Monte Carlo method to search among models and phylogenies to find (1) the tree(s) that best explains a dataset, and (2) the best model(s) of evolution. IPEM Fellows interested in statistical phylogenetics will spend one semester in the Alfaro lab studying Bayesian statistical inference and comparing it to maximum-likelihood and parsimony-based approaches. They will learn (1) how to write computer code to perform Markov-chain Monte Carlo sampling, (2) the role of model selection in phylogenetic inference, (3) how to match analyses to problems and data, and (4) how to perform phylogenetic simulation and test evolutionary hypotheses. They will emerge able to analyze phylogenetic data and statistically test hypotheses of trait evolution. These skills are broadly applicable to many questions of biological and social evolution.

Hunter-gatherer childhoods, emerging diseases and cultural menopause (Barry Hewlett) Hewlett is interested in the evolutionary nature of culture, biocultural nature of human response to emerging diseases, and hunter-gatherer transmission and acquisition of culture. Future projects will include a study of hunter-gatherer play, human responses to Ebola outbreaks in Central Africa and the biocultural evolution of menopause. This project and Lupo's (Area 2) provide a platform for students to design and execute their own research. The projects have field locations at Bagandou, Grima and Ndele in the Central African Republic that are ideal for developing research involving foragers and farmers. Grima and Ndele in the Ngotto Forest Reserve can also be used as staging locales for student projects involving animal populations, including endangered primates such as chimpanzees and gorilla. Lupo and Hewlett are planning a field school to enable American and Central African undergraduates to share education, cultural, and research experience. It will be a collaborative effort involving faculty and students from CURDHACA, a research and curatorial unit of the University of Bangui. Serving as both supervisors and mentors, our IPEM Fellows can share their research ideas and results with these undergraduates, and incorporate them into their research.

Anthropology of Hunter Gatherer Cultural Transmission (Peter Jordan, Mark Collard, et al.) Jordan (through our international partner CECD) has two relevant projects. The first examines the degree to which Siberian languages and other socio-cultural variables are inherited either vertically within communities (via “descent with modification”) vs. horizontally (through intensive culture contact), taking into account ecology, interaction distances, and population densities. The second examines the exceptional cultural and linguistic diversity among Californian and NW Coast Native Americans, where significant local variations in subsistence practices, interaction patterns, local kinship structures and general historical trajectories existed in the recent, documented past. Jordan uses quantitative methods from evolutionary biology to evaluate the degrees to which these different traditions have been reproduced locally vs. exchanged and blended between adjacent communities. Because this research is being carried out from a base in Britain in the Pacific Northwest, there are opportunities for IPEM Fellows and faculty to contribute local expertise to this project. Similar work is being carried out by Collard at the University of British Columbia, with whom we affiliate through the CECD which he helped found. Collard is investigating whether (vertical) branching or (horizontal) blending processes tend to dominate the evolution of human culture. For example, he is statistically comparing cultural data sets from Central Asia, Iran, Neolithic Germany, and eastern North America to similarly sized biological data sets to test whether cultural evolution is more reticulate (web-like, rather than branching) than is biological evolution, as some theorists have argued. Collard is also using phylogenetic methods and other quantitative techniques from biology to infer population history from cultural data. Currently, he and a postdoctoral research fellow at UBC, Briggs Buchanan, are applying cladistics and the Mantel test to a large morphometric dataset derived from projectile points to test competing theories about the route by which Early Paleoindians colonized North America. In a second population history-oriented project, Collard is collaborating with WSU adjunct faculty member Dale Croes on a phylogenetic study of artifacts recovered from dry and waterlogged archaeological sites in the Pacific Northwest Coast with a view to shedding light on the history of the region’s populations over the last several thousand years.

Stylistic variation in Southwestern ceramics (Tim Kohler) Although it has been suggested that stylistic variation is “neutral” in the sense that it has no effects on economic or reproductive success, recent studies have used neutral theory as translated to an archaeological context to document departures from neutrality that indicate social uses for style. Kohler et al. (2004) quantified the similarity over time of ceramic styles among sites in Northern New Mexico, and compared it with a neutral model. They found that conformist transmission accompanied population aggregation under competition. The next research steps are to (1) determine the spatial scales within which conformity is most striking, which will by inference demarcate the sizes and locations of the groups within which social action problems are being solved; and (2) transport the method to SW Colorado to compare the groups identified through this method with the clusters of households (“communities”) that emerge through agent-based modeling and with those identified directly from the archaeological record. IPEM Fellows will be encouraged to participate in both endeavors.

International Kuril Island Paleobiogeography Project: Dynamics of Human and Natural Systems in Historic Perspective (Ben Fitzhugh) Fitzhugh's research bridges Areas 1 and 2. He studies the evolution of cultural systems by focusing on the ways that adaptive behaviors (e.g., foraging strategies, reproductive decisions) interact with environmental contingencies to channel the evolution of novel adaptive mechanisms and social organizations. This archaeological work has been conducted around the Gulf of Alaska and he is now turning to the Russian Kuril Islands where a new NSF Biocomplexity award funds an integrated 5-yr study of the dynamic evolution of coupled human-natural systems. A team of archaeologists, geologists, ecologists, oceanographers atmospheric scientists and modelers (including IPEM faculty member Holman) are studying the role of environmental variation, social network variation, and culturally generated adaptive mechanisms (e.g., technologies) in constraining and facilitating human colonization and persistence in these isolated and vulnerable island settings. The models will use agent-based simulations to predict settlement vulnerability and resilience based on social and cultural characteristics. Advanced stages of the model will incorporate individual- and social-learning mechanisms to explore how these affect adaptation and evolution. This project can provide data, fieldwork, and modeling opportunities for IPEM Fellow training and research.

Sexual selection and divergence in birds and other taxa (Webster) Sexual selection is generally thought to be a key evolutionary force promoting morphological, behavioral, and possibly cultural divergence between populations, and some have proposed that sexual selection may also lead to rapid speciation. Some comparative studies have supported this idea, particularly for groups of taxa, like birds, that appear to be strongly sexually selected. However, few studies of birds have examined the mechanisms that underlie these broad patterns, and it is possible that sexual selection may actually hinder, rather than promote, speciation (e.g., by leading to introgression of sexual traits in zones of secondary contact). This project will address these issues by using phylogeographic approaches to examine divergence of sexual and nonsexual traits across an avian hybrid zone where two populations differing in male sexual signals meet. Work might also include examination of mating behavior within and outside of the hybrid zone, as well as comparison to other human and non-human systems.