Classical Genetics

One claim found in the received historiography of the biometrical school (comprised primarily of Francis Galton, Karl Pearson, and W. F. R. Weldon) is that one of the biometricians' great flaws was their inability to look past their population-focused, statistical, gradualist understanding of evolutionary change – which led, in part, to their ignoring developments in cellular biology around 1900. I will argue, on the contrary, that the work of the biometricians was, from its earliest days, fundamentally concerned with connections between (...) statistical patterns of inheritance and the underlying cellular features that gave rise to them. Such work remained current with contemporary knowledge of chromosomes, cytology, and development; in this article, I explore the first case. The biometricians were thus well positioned to understand the relationship between the patterns of Mendelian inheritance and the statistical distributions with which they primarily occupied themselves. Ignorance of this connection, then, is not the reason why they rejected Mendelism. Further, both Galton and Weldon – though each in their own unique way – decided to turn to biological detail as a way to better justify the generality of their statistical approaches to heredity. Perhaps paradoxically, then, for these biometricians, detail offered an approach to theoretical generality. (shrink)

Historiographical analyses of the development of genetics in the first decade of the 20th century have been to a great extent framed in the context of the Mendelian-Biometrician controversy. Much has been discussed on the nature, origin, development, and legacy of the controversy. However, such a framework is becoming less useful and fruitful. This paper challenges the traditional historiography framed by the Mendelian-Biometrician distinction. It argues that the Mendelian-Biometrician distinction fails to reflect the theoretical and methodological diversity in the controversy. (...) It also argues that that the Mendelian-Biometrician distinction is not helpful to make a full understanding of the development of genetics in the first decade of the twentieth century. (shrink)

It has been widely received that one of Gregor Mendel’s most important contributions to the history of genetics is his novel work on developmental information (for example, the proposal of the famous Mendelian ratios like 1:2:1, 3:1, and 9:3:3:1). This view is well evidenced by the fact that much of early Mendelians’ work in the 1900s focuses on the retrodiction (viz. the re-analysis of the pre-exist data with Mendel’s approach). However, there is no consensus on what Mendel meant by development (...) (Entwicklung). Nor is there an agreement on the interpretation of Mendel’s laws of developmental series (Entwicklungsreihe). This chapter revisits Mendel’s notions of development and developmental series. Firstly, I argue that Mendel’s use of development is greatly influenced by Gärtner’s. Secondly, I show Mendel’s work on developmental series are novel and important for its new ways of experimentation, conceputalisation, and analysis. Thirdly, I argue that Mendel’s laws of developmental information were not about heredity. (shrink)

Alexander Bird indicates that the significance of Thomas Kuhn in the history of philosophy of science is somehow paradoxical. On the one hand, Kuhn was one of the most influential and important philosophers of science in the second half of the twentieth century. On the other hand, nowadays there is little distinctively Kuhn’s legacy in the sense that most of Kuhn’s work has no longer any philosophical significance. Bird argues that the explanation of the paradox of Kuhn’s legacy is that (...) Kuhn took a direction opposite to that of the mainstream of the philosophy of science in his later academic career. This paper aims to provide a new way to understand and develop Kuhn’s legacy by revisiting the development of Kuhn’s philosophy of science in 1970s and proposing a new account of exemplar. Firstly, I propose my diagnosis of Kuhn’s “wrong turning” by identifying Kuhn’s two novel contributions: the introduction of paradigm and the proposal of the incommensurability thesis. Secondly, I argue that Kuhn made a conceptual/terminological turn from paradigm to theory, which undermined Kuhn’s novel contributions. Thirdly, I propose a new articulation of exemplar and propose an exemplar-based approach to analysing the history of science. Finally, I show how the exemplar-based approach can be applied to analyse the history of science by my case study of the early development of genetics. (shrink)

Trying to understand the genome with the classical philosophers. ISBN 978-84-686-6311-1, Bubok, 2015.This book cannot be download at Philpapers due to its 240 MB size . It can be read and download at the web Scribd.

On the current fashion to look after a previous universe to explain the laws of our Universe.Esperando al nuevo Aristóteles, regreso a Henri Bergson y el "Parménides", el otro universo de Plotino. In Spanish.

A briefing of the book "Darwinland" , America Star, 2014.

This research was carried out in order to verify by simulation Mendel’s laws and seek for the clarification, from the author’s point of view, the Mendel-Fisher controversy. It was demonstrated from: the experimental procedure and the first two steps of the Hardy-Weinberg law, that the null hypothesis in such experiments is absolutely and undeniably true. Consequently, repeating hybridizing experiments as those showed by Mendel, it makes sense to expect a highly coincidence between the observed and the expected cell frequencies. By (...) simulation, 30 random samples were generated with size equal to the number of observations reported by Mendel for his single trait trial, in this case, seed shape; assuming complete dominance, with genes A and a; likewise, it was simulated the results for the experiment with two traits, segregating in separate chromosomes, in this case seed shape, as before, and albumen color, with genes B and b, both loci with complete dominance. In the case of a single trait, the data only showed evidence for rejecting the null hypothesis (Ho ) in 1/30 samples, with (P<0.05). In the case of the 30 samples of the two traits experiment, (Ho ) was rejected only on 3/30 times, when it was set a = 0.05. In both simulations there was a high correspondence between the observed and expected cell frequencies, which is simply due to the fact that (Ho ) is true, and under these conditions, that is what would to expect. It was concluded, that Mendel had no reason to manipulate his data in order to make them to coincide with his beliefs. Therefore, in experiment with a single trait, and in experiments with two traits assuming complete dominance, segregation ratios are 3:1; and 9:3:3:1, respectively. Consequently, Mendel’s laws, under the conditions as were described are absolutely valid and universal. (shrink)

Taking as starting point Kuhn’s analysis of science textbooks and its application to Sinnott and Dunn’s (1925), it will be discussed the problem of the existence of laws in biology. In particular, it will be showed, in accordance with the proposals of Darden (1991) and Schaffner (1980, 1986, 1993), the relevance of the exemplars, diagrammatically or graphically represented, in the way in which is carried out the teaching and learning process of classical genetics, inasmuch as the information contained in them, (...) indispensable for the right development of that process, exceeds the information contained in the “laws” linguistically articulated and presented in the textbooks. However, it will be maintained that the information is implicit in the law that according to the structuralist concept of fundamental law and the reconstruction of genetics presented by Balzer & Dawe (1990), and later developed by Balzer & Lorenzano (1997) and Lorenzano (1995, 2000, 2002a) could be considered the fundamental law of classical genetics,the law of matching, clearly identified in this paper. (shrink)

This Ph.D. thesis provides a pilosophical account of the structure of the evolutionary synthesis of the 1930s and 40s. The first, more historical part analyses how classical genetics came to be integrated into evolutionary thinking, highlighting in particular the importance of chromosomal mapping of Drosophila strains collected in the wild by Dobzansky, but also the work of Goldschmidt, Sumners, Timofeeff-Ressovsky and others. The second, more philosophical part attempts to answer the question wherein the unity of the synthesis consisted. I argue (...) that it exemplifies a weak of form of explanatory unification. (shrink)