International Society for History, Philosophy, and Social Studies of Biology


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Program

THURSDAY, JULY 9  /  09:00 - 10:30  /  DS-1540
Individual papers
Modeling Populations and Games

Population genetics and mechanism

Lucas Matthews (University of Utah, United States)

Philosophers of biology have made a very strong case for the role of mechanistic explanation in proximate, process-oriented sciences such as neuroscience (Craver 2007) and molecular biology (Darden 2006). Because these specialized sciences appear highly amenable to mechanistic thinking, questions arise regarding the role of mechanistic explanation in other pattern-oriented domains of investigation that make no explicit appeal to mechanisms. In this paper I investigate population-genetic, statistical approaches to natural selection, with an eye for mechanistic reasoning. I use Tabery’s (2014) conceptions of ‘mechanism-elucidation’ and ‘variation partitioning’ approaches to demonstrate that appeal to mechanisms plays an important role in building evidence for population-genetic, natural selection explanations.


Modeling evolutionary games in populations with demographic structure

Xiangyi Li (Max Planck Institute for Evolutionary Biology, Germany); Stefano Giaimo (Max Planck Institute for Demographic Research, Germany); Annette Baudisch (Max Planck Institute for Demographic Research, Germany); Arne Traulsen (Max Planck Institute for Evolutionary Biology, Germany)

Classic life history models are often based on optimization algorithms, focusing on the adaptation of survival and reproduction to the environment, while neglecting frequency dependent interactions in the population. Evolutionary game theory, on the other hand, studies frequency dependent strategy interactions, but usually omits life history and the demographic structure of the population. Here we show how an integration of both aspects can substantially alter the underlying evolutionary dynamics. We study the replicator dynamics of strategy interactions in life stage structured populations. Individuals have two basic strategic behaviours, interacting in pairwise games. A player may condition behaviour on the life stage of its own, or that of the opponent, or the matching of life stages between both players. A strategy is thus defined as the set of rules that determines a player’s life stage dependent behaviours. We show that the diversity of life stage structures and life stage dependent strategies can promote each other, and the stable frequency of basic strategic behaviours can deviate from game equilibrium in populations with life stage structures.


The explanatory payoffs of multiple realization in cognitive neuroscience

Maria Serban** (University of Pittsburgh, United States)

Given a stable higher-level theory and a theory pitched toward the lower-level of organization of a biological system, the doctrine of multiple realization claims that there are one-to-many mappings from the unified (and perhaps homogeneous) higher-level properties to the heterogeneous lower-level properties of the system. The multiple realization doctrine has been traditionally taken to license a strong thesis about the autonomy of psychology from neurobiology and to set an antireductionist agenda for philosophy of cognitive science in general (Putnam 1965; Fodor 1974). However, critics of multiple realization have contested the strong anti-reductionist consequences of the thesis. Their objections targeted both the conceptual arguments for multiple realization (Sober 1999) and the lack of empirical support for the doctrine within cognitive neuroscience (Bechtel and Mundale 1999). In response, I argue that current scientific research provides ample support for the multiple realization thesis in both biology and cognitive neuroscience. Drawing a comparison between the degeneracy thesis (Tononi, Sporns, and Edelman 1999; Edelman and Gally 2001; Price and Friston 2002; Mason 2014) and the multiple realization thesis allows us to refine some of the features and implications of adopting multiple realization as a viable research hypothesis in cognitive neuroscience. In order to illustrate the methodological and explanatory payoffs of the multiple realization thesis I rely on research on the phenomenon of recovery of language functions. This case study illustrates that the collaboration between different cognitive modeling paradigms (the lesion-deficit model, functional imaging studies of normal adult subjects and developmental models of brain function recovery) provides ample support for the multiple realization or degeneracy of higher-level cognitive functions. In this context, I show how the thesis of multiple realization promotes the development of mixed-level explanatory strategies for explaining the properties and behaviors exhibited by complex biological systems at higher (and more abstract) levels of organization.