Robert G. Wallace

Organisms, organizations and interactions: an information theory approach to biocultural evolution.

The language metaphor of theoretical biology, proposed by Waddington in 1972, provides a basis for the formal examination of how different self-reproducing structures interact in an extended evolutionary context. Such interactions have become central objects of study in fields ranging from human evolution-genes and culture-to economics-firms, markets and technology. Here we use the Shannon-McMillan Theorem, one of the fundamental asymptotic relations of probability theory, to study the weakest and hence most universal, forms of interaction between generalized languages. We propose that the co-evolving gene-culture structure that permits human ultra-sociality emerged in a singular coagulation of genetic and cultural languages, in the general sense of the word. Human populations have since hosted series of culture-only speciations and coagulations, events that, in this formulation, do not become mired in the meme concept.

AIDS in the HAART era: New York's heterogeneous geography

During the 1990s, the number of new AIDS cases in New York City, USA, declined precipitously. The declines, beginning before highly active antiretroviral therapy (HAART) was introduced, were geographically heterogeneous across two New York City boroughs analyzed. From 1993 to 1998, zip codes in Lower Manhattan, with large white and affluent populations, had declines as much as 55% more than the rest of Manhattan. Bronx zip codes underwent still lesser declines. Declines also differed within zip codes among subpopulations. White zip code populations tended to have greater declines than Latino populations, which in turn tended to have greater declines than black populations. According to bivariate and stepwise regressions, an array of socioeconomic and community stress variables acted in combination on the decline in New York AIDS. Manhattans declines in total AIDS incidence were primarily defined by changes in AIDS incidence for whites and for men who have sex with men, racial segregation, and the proportions of households in upper income classes and under rent stress. Bronx declines in total AIDS are principally explained by a broader range of income classes, and social instability as marked by housing overcrowding and cirrhosis and drug mortalities. Whatever the combination of proximate causes for the decline in AIDS incidence in 1990s New York (educational campaigns, HAART, demographic stochasticity), the decline was shaped by the citys socioeconomic structure and political and ecological history. That structure and history generates the geographically defined aggregates of behaviors that promote or impede AIDS decline. Such spatial heterogeneity may provide for HIV refugia, areas where the virus can weather the epidemics contraction, a troubling possibility with the accelerating microbicidal failures of combination therapies.

Immune cognition and vaccine strategy: beyond genomics

I.R. Cohens work on immune cognition has profound implications for vaccine strategies when simple elicitation of sterilizing immunity fails, given Nisbetts analysis showing that cognition by the central nervous system is culturally determined. We reinterpret West African cultural variation in immune response to malaria, and the US cultural variation in HIV transmission, from this perspective, which does not reify race.

The shape of space: applying geometric morphometrics to geographic data

Another means is proposed for displaying epistatic change in spatially structured ecologies. The approach uses techniques developed in geometric morphometrics, a relatively new discipline centered on mapping change in bone and other morphologies through evolutionary time across taxa. Warps analysis is introduced and its terms and protocols explained. An example of warps analysis as applied to geographic data is presented. The example focuses on the AIDS epidemic in two boroughs of New York City. Female adult AIDS incidence and percentage newborns exposed to HIV, by zip code for the years 1991 – 98, are used to generate annual configurations within an ecological parameter space. A warps analysis of those configurations indicates a clear shift in the relative positions of Manhattan zip codes during the 1990s. The analysis shows the relative positions of two subareas comprised of Harlem and Lower Manhattan zip codes were displaced in contrary directions in the parameter space with the introduction of antiretroviral combination therapies (HAART). In contrast, a warps analysis of the Bronxs AIDS parameter space shows few definable zip code groupings or temporal trends before or with HAART. The promises and problems in applying warps analysis to geographic data are discussed.