A stochastic individual based model,SCHISTOX,has been developed for the study of schistosome transmission dynamics and the impact of control by mass drug administration.More novel aspects that can be investigated incl...A stochastic individual based model,SCHISTOX,has been developed for the study of schistosome transmission dynamics and the impact of control by mass drug administration.More novel aspects that can be investigated include individual level adherence and access to treatment,multiple communities,human sex population dynamics,and implementation of a potential vaccine.Many of the model parameters have been estimated within previous studies and have been shown to vary between communities,such as the age-specific contact rates governing the age profiles of infection.However,uncertainty remains as there are wide ranges for certain parameter values and a few remain relatively unknown.We analyse the model dynamics by parameterizing it with published parameter values.We also discuss the development of SCHISTOX in the form of a publicly available open-source GitHub repository.The next key development stage involves validating the model by calibrating to epidemiological data.展开更多
Behavioral ＂traditions＂, i.e. behavioral patterns that are acquired with the aid of social learning and that are relatively stable in a group, have been observed in several species. Recently, however, it has been qu...Behavioral ＂traditions＂, i.e. behavioral patterns that are acquired with the aid of social learning and that are relatively stable in a group, have been observed in several species. Recently, however, it has been questioned whether non-human social learning is faithful enough to stabilize those patterns. The observed stability could be interpreted as a result of various constraints that limit the number of possible alternative behaviors, rather than of the fidelity of transmission mechanisms. Those constraints can be roughly described as ＂internal＂, such as mechanical （bodily） properties or cognitive limitations and predispositions, and ＂ex- ternal＂, such as ecological availability or pressures. Here we present an evolutionary individual-based model that explores the re- lationships between the evolution of faithful social learning and behavioral constraints, represented both by the size of the beha- vioral repertoire and by the ＂shape＂ of the search space of a given task. We show that the evolution of high-fidelity transmission mechanisms, when associated with costs （e.g. cognitive, biomechanical, energetic, etc.）, is only likely if the potential behavioral repertoire of a species is large and if the search space does not provide information that can be exploited by individual learning. Moreover we show how stable behavioral patterns （＂traditions＂） can be achieved at the population level as an outcome of both high-fidelity and low-fidelity transmission mechanisms, given that the latter are coupled with a small behavioral repertoire or with a search space that provide substantial feedback. Finally, by introducing the possibility of environmental change, we show that intermediate rates of change favor the evolution of faithful social learning展开更多
基金All authors gratefully acknowledge funding of the NTD Modelling Consortium by the Bill and Melinda Gates Foundation[OPP1184344].
文摘A stochastic individual based model,SCHISTOX,has been developed for the study of schistosome transmission dynamics and the impact of control by mass drug administration.More novel aspects that can be investigated include individual level adherence and access to treatment,multiple communities,human sex population dynamics,and implementation of a potential vaccine.Many of the model parameters have been estimated within previous studies and have been shown to vary between communities,such as the age-specific contact rates governing the age profiles of infection.However,uncertainty remains as there are wide ranges for certain parameter values and a few remain relatively unknown.We analyse the model dynamics by parameterizing it with published parameter values.We also discuss the development of SCHISTOX in the form of a publicly available open-source GitHub repository.The next key development stage involves validating the model by calibrating to epidemiological data.
文摘Behavioral ＂traditions＂, i.e. behavioral patterns that are acquired with the aid of social learning and that are relatively stable in a group, have been observed in several species. Recently, however, it has been questioned whether non-human social learning is faithful enough to stabilize those patterns. The observed stability could be interpreted as a result of various constraints that limit the number of possible alternative behaviors, rather than of the fidelity of transmission mechanisms. Those constraints can be roughly described as ＂internal＂, such as mechanical （bodily） properties or cognitive limitations and predispositions, and ＂ex- ternal＂, such as ecological availability or pressures. Here we present an evolutionary individual-based model that explores the re- lationships between the evolution of faithful social learning and behavioral constraints, represented both by the size of the beha- vioral repertoire and by the ＂shape＂ of the search space of a given task. We show that the evolution of high-fidelity transmission mechanisms, when associated with costs （e.g. cognitive, biomechanical, energetic, etc.）, is only likely if the potential behavioral repertoire of a species is large and if the search space does not provide information that can be exploited by individual learning. Moreover we show how stable behavioral patterns （＂traditions＂） can be achieved at the population level as an outcome of both high-fidelity and low-fidelity transmission mechanisms, given that the latter are coupled with a small behavioral repertoire or with a search space that provide substantial feedback. Finally, by introducing the possibility of environmental change, we show that intermediate rates of change favor the evolution of faithful social learning
