Robert Walker

Postdoctoral Researcher

Integrative Primate Socioecology, MPI-EVAN

Curriculum Vitae

Apartment for Sale

Research and Teaching Interests

I am primarily a human behavioral ecologist, and my research attempts to understand behavioral and life-history variation among humans from a socioecological and evolutionary perspective (see PDFs below). My research and teaching goals focus on situating modern human variation in development, behavior and life-history against a backdrop of variation in other primates. For example, I am especially interested in using comparative analyses to study the evolution of long, slow-growing (yet large-brained) juvenile periods in humans as this is arguably the most derived human trait, driven by our early age at weaning and delayed growth spurt. In another line of inquiry, research with colleague Marcus Hamilton has uncovered a self-similar (or fractal-like) social structure in hunter-gatherer societies. Moreover, humans in a wide variety of contexts show increasingly efficient use of territory in larger populations which, along with the self-similarity in social structure, intriguingly suggest that human societies can be considered complex adaptive systems, perhaps even analogous to "super-organisms" in some regards.

In addition to statistical analyses and optimality modeling, I also enjoy fieldwork in South America. I have conducted research in Brazil, Paraguay, Bolivia, and Suriname with hunter-gatherers and subsistence horticulturalists. I loosely collaborate with an international team of researchers working around the globe and who share a common interest in quantifying age-specific rates of growth, fertility and mortality. My colleagues and I have found evidence that high mortality associates with population density, faster body growth, and earlier menarche and reproduction. There is also evidence for a trade-off between number and size of offspring across and within societies, an empirical pattern well-supported in other animals. I use these growing databases as a keystone for introducing students to a wide variety of topics that relate to the evolution of growth, senescence, mating and parenting. Opportunities abound in South America and around the world for students to conduct research in some of these ongoing fieldsites as well as develop new fieldsites in other communities. In my courses, I strongly encourage students to gain hands-on experience in data collection and analyses, placing confidence in their ability to conduct high-quality, publishable research.

Publications (PDFs)

13. Walker, R. S., M. Gurven, O. Burger, M. J. Hamilton (under review) The trade-off between number and size of offspring in humans and other primates.

12. Walker, R. and M. J. Hamilton (in press) Life history consequences of density dependence and the evolution of human body sizes. Current Anthropology.

11. Hamilton, M. J., B. Milne, R. S. Walker, O. Burger, and J. Brown (2007) The complex nature of hunter-gatherer social networks. Proceedings of the Royal Society of London, Series B 274:2195-2202.

10. Hamilton, M. J., B. Milne, R. S. Walker, and J. Brown (2007) Nonlinear scaling of space use in human hunter-gatherers. Proceedings of the National Academy of Sciences, USA 104:4765-4769.

9. Hill, K., A. M. Hurtado, and R. S. Walker (2007) High adult mortality among Hiwi hunter-gatherers: Implications for human evolution. Journal of Human Evolution 52:443-454.

8. Walker, R. S., O. Burger, J. Wagner, and C. Von Rueden (2006) Evolution of brain size and juvenile periods in primates. Journal of Human Evolution 51:480-89.

7. Walker, R. S., M. Gurven, K. Hill, A. Migliano, N. Chagnon, R. De Souza, G. Djurovic, R. Hames, A. M. Hurtado, H. Kaplan, K. Kramer, W. J. Oliver, C. Valeggia, and T. Yamauchi (2006) Growth rates and life histories in twenty-two small-scale societies. American Journal of Human Biology 18:295-311 (Feature Article).

6. Walker, R. S., K. Hill, O. Burger, and A. M. Hurtado (2006) Life in the slow lane revisited: Ontogenetic separation between chimpanzees and humans. American Journal of Physical Anthropology 129:577-583.

5. Gurven, M. and R. S. Walker (2006) Energetic demand of multiple dependents and the evolution of slow human growth. Proceedings of the Royal Society of London, Series B 273:835-841.

4. Burger, O., M. Hamilton, and R. S. Walker (2005) The prey as patch model: A marginal gains curve for vertebrate prey. Journal of Archaeological Science, 32:1147-1158.

3. Walker, R. S. and K. Hill (2003) Modeling growth and senescence in physical performance among the Ache of eastern Paraguay. American Journal of Human Biology, 15:196-208.

2. Walker, R. S., K. Hill, H. Kaplan, and G. MacMillan (2002) Age-dependency in hunting ability among the Ache of eastern Paraguay. Journal of Human Evolution 42:639-657.

1. Todd, L. C., D. C. Jones, R. S. Walker, P. Burnett, and J. Eighmy (2001) Late archaic bison hunters in Northern Colorado: 1997-1999 Excavations at the Kaplan-Hoover Bison Bonebed (5LR3953). Plains Anthropologist 46: 125-147.