Abstract # 14:

Scheduled for Saturday, September 17, 2011 09:30 AM-09:45 AM: Session 4 (Meeting Room 410) Oral Presentation


T. Olivier
Green Creek Paradigms, LLC, 4632 Green Creek Road, Schuyler, Virginia 22969-1602, USA

This study examines infectious disease dynamics and associated genetic, demographic and social processes in simulated monkey populations. It models gene frequency changes that reduce impacts of the disease on infected individuals. Simulations were built using CRITTRZ, a simulation library developed by the author. An interface to the Idrisi geographic information system (GIS) allowed use of GIS data layers for representation of model landscapes.  Simulated populations contained subpopulations resembling cercopithecine multimale groups. Reproduction and survival rates were density-dependent.  Starting populations contained 659 individuals divided into 28 social groups, with 280 members infected.  The genotype at an autosomal locus potentially affected likelihood of survival of infected individuals.   The risk of dying from disease in one time period for infected individuals heterozygous for a selected-against allele equaled a specified selection coefficient.  Infected individuals homozygous for this allele had a risk of dying twice the selection coefficient.    Initial frequency of the selected-against allele was 0.68. Simulation series employing selection coefficients of 0, 0.2 and 0.4 were conducted.  In the series with selection, population sizes and group numbers dropped noticeably in early time periods.  Group fusions were common then. Over time, population sizes and group numbers recovered.  Frequencies of the selected-against allele declined.  Infected individuals remained widespread.   This study shows that genetic adaptations of natural populations to disease may entail shifts in their social and demographic states.