Molecular clocks based upon amino acid sequences in proteins have played a major role in the clarification of evolutionary phylogenies. Creationist criticisms of these methods sometimes rely upon data that might initially seem to be paradoxical. For example, human cytochrome c differs from that of an alligator by 13 amino acids but differs by 14 amino acids from a much more closely related primate, Otolemur garnettii. The apparent anomaly is resolved by taking into consideration the variable substitution rate of cytochrome (...) c, particularly among primates. This paper traces some of the history of extensive research into the topic of rate heterogeneity in cytochrome c including data from cytochrome c pseudogenes. (shrink)

We argue that the mathematization of science should be understood as a normative activity of advocating for a particular methodology with its own criteria for evaluating good research. As a case study, we examine the mathematization of taxonomic classification in systematic biology. We show how mathematization is a normative activity by contrasting its distinctive features in numerical taxonomy in the 1960s with an earlier reform advocated by Ernst Mayr starting in the 1940s. Both Mayr and the numerical taxonomists sought to (...) formalize the work of classification, but Mayr introduced a qualitative formalism based on human judgment for determining the taxonomic rank of populations, while the numerical taxonomists introduced a quantitative formalism based on automated procedures for computing classifications. The key contrast between Mayr and the numerical taxonomists is how they conceptualized the temporal structure of the workflow of classification, specifically where they allowed meta-level discourse about difficulties in producing the classification. (shrink)

The Bermuda Principles for DNA sequence data sharing are an enduring legacy of the Human Genome Project. They were adopted by the HGP at a strategy meeting in Bermuda in February of 1996 and implemented in formal policies by early 1998, mandating daily release of HGP-funded DNA sequences into the public domain. The idea of daily sharing, we argue, emanated directly from strategies for large, goal-directed molecular biology projects first tested within the “community” of C. elegans researchers, and were introduced (...) and defended for the HGP by the nematode biologists John Sulston and Robert Waterston. In the C. elegans community, and subsequently in the HGP, daily sharing served the pragmatic goals of quality control and project coordination. Yet in the HGP human genome, we also argue, the Bermuda Principles addressed concerns about gene patents impeding scientific advancement, and were aspirational and flexible in implementation and justification. They endured as an archetype for how rapid data sharing could be realized and rationalized, and permitted adaptation to the needs of various scientific communities. Yet in addition to the support of Sulston and Waterston, their adoption also depended on the clout of administrators at the US National Institutes of Health and the UK nonprofit charity the Wellcome Trust, which together funded 90% of the HGP human sequencing effort. The other nations wishing to remain in the HGP consortium had to accommodate to the Bermuda Principles, requiring exceptions from incompatible existing or pending data access policies for publicly funded research in Germany, Japan, and France. We begin this story in 1963, with the biologist Sydney Brenner’s proposal for a nematode research program at the Laboratory of Molecular Biology at the University of Cambridge. We continue through 2003, with the completion of the HGP human reference genome, and conclude with observations about policy and the historiography of molecular biology. (shrink)

This paper aims to understand how and why tree diagrams are of central importance to microbiome scientists in their practices of meaning making. The interfaces that scientists use are, in fact, topological structures that organize the genetic data generated by sequencing technology. They establish relationships among microbes and also between microbes and the conditions of the ecological niche they help construct. The tree structure is a powerful _topos_ of knowledge organization in Western culture. However, biomolecular research has revealed the existence (...) of horizontal gene exchange among microbes and other merging forms; these cast doubt on the tree as a valid representational metaphor for the tangle of the microbial world and help to overcome neo-Darwinism. This essay analyzes the software and interfaces used by microbiome scientists as tools for organizing knowledge that shape how we see human-microbe relationships, while escaping a representational function. While trees have long been considered representative forms of visualization of an evolutionary paradigm, we emphasize the non-illustrative and heuristic power of these interfaces, which, although steeped in centuries of reflection and debate on evolutionary theories, respond more to a diagrammatic logic: tools for discovering the new from genetic “black matter” and for exploring new forms of relationships between microbes and humans. (shrink)

Reconstructing the genetic traits of the Last Common Ancestor and the Tree of Life are two examples of the reaches of contemporary molecular phylogenetics. Nevertheless, the whole enterprise has led to paradoxical results. The presence of Lateral Gene Transfer poses epistemic and empirical challenges to meet these goals; the discussion around this subject has been enriched by arguments from philosophers and historians of science. At the same time, a few but influential research groups have aimed to reconstruct the LCA with (...) rich-in-detail hypotheses and high-resolution gene catalogs and metabolic traits. We argue that LGT poses insurmountable challenges for detailed and rich in details reconstructions and propose, instead, a middle-ground position with the reconstruction of a slim LCA based on traits under strong pressures of Negative Natural Selection, and for the need of consilience with evidence from organismal biology and geochemistry. We defend a cautionary perspective that goes beyond the statistical analysis of gene similarities and assumes the broader consequences of evolving empirical data and epistemic pluralism in the reconstruction of early life. (shrink)

This article is a study of the role and use of evidence in the evaluation of claims in the historical sciences. In order to do this, I develop a “snapshot” approach to Toulmin schemas. This framework is applied to the case of Archezoa, an initially supported then eventually rejected hypothesis in evolutionary biology. From this case study, I criticize Cleland’s “smoking gun” account of the methodology of the historical sciences. I argue that Toulmin schemas are conceptually precise tools that allow (...) for the building of enriched reconstructions of evidential reasoning. From the application of this framework, I discuss three ways in which the construction and use of facts in the historical sciences are theory-laden. Despite its inherent limits, TS are heuristically useful tools to identify epistemic moves that could be further investigated. It also sheds light on the positive roles of speculation in the historical sciences. Finally, I argue that it provides a context-specific and individuated understanding of hypothesis evaluation in the historical sciences. Overall, I think the application of Toulmin schemas to cases of evidential reasoning in the historical sciences is a promising descriptive and heuristic tool for philosophers of science. (shrink)

Erwin Schrödinger’s 1944 publication What is Life? is a classic of twentieth century science writing. In his book, Schrödinger discussed the chromosome fibre as the seat of heredity and variation thanks to a hypothetical aperiodic structure – a suggestion that famously spurred on a generation of scientists in their pursuit of the gene as a physico-chemical entity. While historical attention has been given to physicists who were inspired by the book, little has been written about its biologist readers. This paper (...) examines the case of the English evolutionary botanist and cytologist Irène Manton, who took an interest in What is Life? for its relevance to her own research in chromosome structure as a clue to plant phylogeny. Drawing on recently discovered correspondence between Manton and Schrödinger, the paper reconstructs Manton ‘s path to the book and her response to it by way of throwing new light on a pivotal moment in the history of the debate on chromosome structure. (shrink)

This paper examines the controversy that followed the 1987 publication of Joseph Greenberg's book, Language in the Americas, attending to the role of language and linguistic research within overlapping disciplinary traditions. With this text, Greenberg presented a macro‐level tripartite classification that opposed then dominant fine‐grained analyses recognizing anywhere from 150 to 200 distinct language families. His proposal was the subject of a landmark conference, examining strengths and weaknesses, the unpublished proceedings of which are presented here for the first time. For (...) specialists in the anthropological and comparative‐historical study of Indigenous American languages, Greenberg's intervention highlighted the tension between language, conceived as an abstract object of study, and languages, understood to be carriers of specific cultural knowledge. For physical anthropologists and archaeologists, his theory was initially fortuitous on programmatic, substantive, and methodological grounds. The essay will show how interdisciplinary appeals were figured by supporters as a virtue, and by critics as a vice. The essay further highlights ethical reasons for integrating historical narratives of science and the humanities. (shrink)

Cet article propose une étude conceptuelle d’une pratique scientifique. L’analyse phylogénétique, méthode phare en biologie de l’évolution, permet d’inférer les relations évolutives entre différentes espèces ou organismes. De nos jours, elle fait souvent intervenir l’usage de données moléculaires, dont les résultats sont appelés des phylogénies moléculaires. Comment caractériser cette pratique? Nous commençons par une présentation de la méthode, en la découpant en quatre étapes : l’identification puis l’alignement de séquences homologues ; la construction puis l’interprétation d’un arbre phylogénétique. Nous montrons (...) que l’analyse phylogénétique n’est pas une expérimentation, et donc n’appartient pas au « style de laboratoire », tel que défini par Hacking. Elle ne correspond pas non plus à une méthode typique des sciences historiques, telle que décrite par Cleland. Bien que la correspondance de l’analyse phylogénétique avec ces catégorisations ne soit que partielle, nous défendons l’utilité de chacune de ces confrontations pour souligner des aspects distincts de cette pratique. Nous remettons aussi en cause l’idée d’une séparation méthodologique nette entre sciences expérimentales et sciences historiques. (shrink)

ArgumentThis paper analyzes the research strategies of three different cases in the study of human genetics in Mexico – the work of Rubén Lisker in the 1960s, INMEGEN's mapping of Mexican genomic diversity between 2004 and 2009, and the analysis of Native American variation by Andrés Moreno and his colleagues in contemporary research. We make a distinction between an approach that incorporates multiple disciplinary resources into sampling design and interpretation (unpacking), from one that privileges pragmatic considerations over more robust multidisciplinary (...) analysis (flattening). These choices have consequences for social, demographic, and biomedical practices, and also for accounts of genetic variation in human populations. While the former strategyunpacksfine-grained genetic variation – favoring precision and realism, the latter tends toflattenindividual differences and historical depth in lieu of generalization. (shrink)

The use of molecules and reactions as evidence, markers and/or traits for evolutionary processes has a history more than a century long. Molecules have been used in studies of intra-specific variation and studies of similarity among species that do not necessarily result in the analysis of phylogenetic relations. Promoters of the use of molecular data have sustained the need for quantification as the main argument to make use of them. Moreover, quantification has allowed intensive statistical analysis, as a condition and (...) a product of increasing automation. All of these analyses are subject to the methodological anxiety characteristic of a community in search of objectivity. It is in this context that scientists compared and evaluated protein and nucleic acid sequence data with other types of molecular data – including immunological, electrophoretic and hybridization data. This paper argues that by looking at long-term historical processes, such as the use of molecular evidence in evolutionary biology, we gain valuable insights into the history of science. In that sense, it accompanies a growing concern among historians for big-pictures of science that incorporate the fruitful historical research on local cases of the last decades. (shrink)

This is the story, told in the light of a new analysis of historical data, of a mathematical biology problem that was explored in the 1930s in Thomas Morgan’s laboratory at the California Institute of Technology. It is one of the early developments of evolutionary genetics and quantitative phylogeny, and deals with the identification and counting of chromosomal inversions in Drosophila species from comparisons of genetic maps. A re-analysis of the data produced in the 1930s using current mathematics and computational (...) technologies reveals how a team of biologists, with the help of a renowned mathematician and against their first intuition, came to an erroneous conclusion regarding the presence of phylogenetic signals in gene arrangements. This example illustrates two different aspects of a same piece: the appearance of a mathematical in biology problem solved with the development of a combinatorial algorithm, which was unusual at the time, and the role of errors in scientific activity. Also underlying is the possible influence of computational complexity in understanding the directions of research in biology. (shrink)

Cet article propose une étude conceptuelle d’une pratique scientifique. L’analyse phylogénétique, méthode phare en biologie de l’évolution, permet d’inférer les relations évolutives entre différentes espèces ou organismes. De nos jours, elle fait souvent intervenir l’usage de données moléculaires, dont les résultats sont appelés des phylogénies moléculaires. Comment caractériser cette pratique? Nous commençons par une présentation de la méthode, en la découpant en quatre étapes : (1) l’identification puis (2) l’alignement de séquences homologues (descendants d’un ancêtre commun) ; (3) la construction (...) puis (4) l’interprétation d’un arbre phylogénétique. Nous montrons que l’analyse phylogénétique n’est pas une expérimentation, et donc n’appartient pas au « style de laboratoire », tel que défini par Hacking. Elle ne correspond pas non plus à une méthode typique des sciences historiques, telle que décrite par Cleland. Bien que la correspondance de l’analyse phylogénétique avec ces catégorisations ne soit que partielle, nous défendons l’utilité de chacune de ces confrontations pour souligner des aspects distincts de cette pratique. Nous remettons aussi en cause l’idée d’une séparation méthodologique nette entre sciences expérimentales et sciences historiques. (shrink)

Using the Burgess Shale controversies as a case-study, this paper argues that controversies within different domains may interact as to create a situation of "complicated intricacies," where the practicing scientist has to navigate through a context of multiple thought collectives. To some extent each of these collectives has its own dynamic complete with fairly negotiated standards for investigation and explanation, theoretical background assumptions and certain peculiarities of practice. But the intellectual development in one of these collectives may "spill over" having (...) far reaching consequences for the treatment of apparently independent epistemic problems that are subject of investigation in other thought collectives. For the practicing scientist it is necessary to take this complex web of interactions into account in order to be able to navigate in such a situation. So far most studies of academic science have had a tendency to treat the practicing scientist as members of a single (enclosed) thought collective that stands intellectually isolated from other similar entities unless the discipline was in a state of crisis of paradigmatic proportions. The richness and complexity of Burgess Shale debate shows that this encapsulated kind of analysis is not enough. (shrink)