Missing concepts in natural selection theory reconstructions

Abstract

The concept of fitness has generated a lot of discussion in philosophy of biology. There is, however, relative agreement about the need to distinguish at least two uses of the term: ecological fitness on the one hand, and population genetics fitness on the other. The goal of this paper is to give an explication of the concept of ecological fitness by providing a reconstruction of the theory of natural selection in which this concept was framed, that is, based on the way the theory was put to use in Darwin's main texts. I will contend that this reconstruction enables us to account for the current use of the theory of natural selection. The framework presupposed in the analysis will be that of metatheoretical structuralism. This framework will provide both a better understanding of the nature of ecological fitness and a more complete reconstruction of the theory. In particular, it will provide what I think is a better way of understanding how the concept of fitness is applied through heterogeneous cases. One of the major advantages of my way of thinking about natural selection theory is that it would not have the peculiar metatheoretical status that it has in other available views. I will argue that in order to achieve these goals it is necessary to make several concepts explicit, concepts that are frequently omitted in usual reconstructions.

The key role of underlying theories for scientific explanations. A darwinian case study

“…"Adaptation" is a multivocal notion. It is sometimes used to name those functional traits that emerged by natural selection, that is, traits whose origin are indeed explained by natural selection; while at other times, it is used to name the functional traits whose origin natural selection aims to explain (Burian 1992;Ginnobili 2016Ginnobili , 2019West-Eberhard 1992). The use of the term that interests us here is the second.…”

Dos usos de los modelos de optimalidad en las explicaciones por selección natural

“…En esta sección, siguiendo a Ginnobili (2010Ginnobili ( , 2014Ginnobili ( , 2016 presentaremos dos formas en las que la selección natural es utilizada. A veces, los autores presentan a la selección natural como un proceso que involucra muchas generaciones, con el objetivo de explicar el origen de las adaptaciones, es decir, para explicar cómo ciertas poblaciones de organismos han adquirido rasgos altamente especializados, que les permiten sobrevivir y reproducirse de manera altamente efectiva en el ambiente en el que viven (Kitcher 1993, Skipper & Millstein 2005.…”

“…Por supuesto, si Ginnobili (2010Ginnobili ( , 2016 tienen la razón, entonces determinar las diferencias en la eficacia con la que una función es desarrollada también nos permitiría determinar las diferencias de fitness, a través de la aplicación del PNS (así como uno puede determinar las aceleraciones a partir de fuerzas y masas, y la aplicación de la segunda ley de Newton). Pero el punto sería que esto sólo sería un modo indirecto de determinar a las diferencias de fitness, y por lo tanto la historia propensivista (la cual toma a esta relación como una más directa) sería una caracterización metateórica inadecuada de esta relación -al menos en lo que concierne a OFT-.…”

Optimality Models and the Propensity Interpretation of Fitness

“…In that way, determining currency values in an optimality model could allow us to establish a fitness ranking between different kinds of organisms, though not their precise fitness values. Some authors (Casanueva 2011;Ginnobili 2016) have tried to make this connection more explicit by introducing a second conditional to the PNS, which goes from the optimality / environmental effectiveness of a trait to fitness. For example, Ginnobili formulates the PNS as follows:…”