Mendelian

To test Mendelian inheritance of monohybrid and dihybrid crosses and sex-linked inheritance, four different crosses were conducted in this experiment. Drosophila melanogaster was used, as it is a model organism in the field of genetics because of its many convenient qualities; D. melanogaster has a short life cycle, is easy to breed and take care of, and is readily available and affordable (Brooker, 2014). The cross results using D. melanogaster in this experiment are expected to follow the Mendelian patterns of inheritance in monohybrid, dihybrid, and sex-linked crosses.

This dissertation brings a contribution to the philosophical debate on adaptive landscapes, an influent "model" or "metaphor" in evolutionary biology. Some elements of innovation are: the distinction between native and migrant metaphor; a processual and communicational idea on what the Modern Synthesis was, and on what role a metaphor could have played in it; a view (taken by Richard Lewontin) of the disunity and theoretical structure of population genetics; the distinction between “adaptive surfaces” (mainly metaphors) and “combination spaces”, two terms normally conflated in the word “landscape”; an analysis of what bridges (including heuristics) may be cast between equations of gene frequency and the genotype space that, due to its huge dimensionality, cannot be handled by mathematics; a specified vocabulary to be used to clear the adaptive landscapes debate, accompanied by a plea in favor of a pragmatic approach - for example, the plurality of available notions of model forces us to choose one notion and see where it brings, otherwise we get stuck in confused, endless debates; an updated analytical comment of recent landscapes - Dobzhansky, Simpson, Dawkins but also the proliferation of combination spaces used in evolutionary biology to address a great variety of problems; the vision (got by Sergey Gavrilets) of a patchwork of tools finally making Mendelian population suitable model also for speciation; the exact position of holey landscapes in this patchwork, and the idea that scientists’s questions - like “how possibly” questions - matter in accessing this patchwork and in deciding “what explains” and “what describes” what in the world; the direct response to some mistakes Massimo Pigliucci made, I think, in his assessment of the adaptive landscape; an analysis of the Extended Evolutionary Synthesis project at its present stage, and some reflections on the conditions that will allow such a project to give a fair treatment and a good position to tools from the past, like the adaptive landscapes.

Keywords: evolution, biology, philosophy of science, model, metaphor, synthesis, adaptive or fitness landscapes, surfaces, visualization, dobzhansky, simpson, dawkins, gavrilets, j huxley, pigliucci, modern and extended evolutionary synthesis, population genetics, mendelian combination space

What are scientific theories and how should they be represented? In this paper I propose a causal-structural account, according to which scientific theories are to be represented as sets of interrelated causal and credal nets. In contrast with other accounts of scientific theories (such as Sneedian structuralism, Kitcher's unificationist view, and Darden's theory of theoretical components), this leaves room for causality to play a substantial role. As a result, an interesting account of explanation is provided which sheds light on explanatory unification within a causalist framework. The theory of classical genetics is used as a case study.