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1.
Annu Rev Genet ; 52: 1-20, 2018 11 23.
Artigo em Inglês | MEDLINE | ID: mdl-30192637

RESUMO

My trajectory to becoming a plant biologist was shaped by a complex mix of scientific, political, sociological, and personal factors. I was trained as a microbiologist and molecular biologist in the late 1960s and early 1970s, a time of political upheaval surrounding the Vietnam War. My political activism taught me to be wary of the potential misuses of scientific knowledge and to promote the positive applications of science for the benefit of society. I chose agricultural science for my postdoctoral work. Because I was not trained as a plant biologist, I devised a postdoctoral project that took advantage of my microbiological training, and I explored using genetic technologies to transfer the ability to fix nitrogen from prokaryotic nitrogen-fixing species to the model plant Arabidopsis thaliana with the ultimate goal of engineering crop plants. The invention of recombinant DNA technology greatly facilitated the cloning and manipulation of bacterial nitrogen-fixation ( nif) genes, but it also forced me to consider how much genetic engineering of organisms, including human beings, is acceptable. My laboratory has additionally studied host-pathogen interactions using Arabidopsis and the nematode Caenorhabditis elegans as model hosts.


Assuntos
Arabidopsis/genética , Caenorhabditis elegans/genética , Interações Hospedeiro-Patógeno/genética , Simbiose/genética , Animais , Arabidopsis/microbiologia , Biologia/história , Caenorhabditis elegans/microbiologia , História do Século XX , História do Século XXI , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/patogenicidade , Fixação de Nitrogênio/genética , Sinorhizobium meliloti/genética , Sinorhizobium meliloti/patogenicidade
2.
Cell ; 146(6): 851-4, 2011 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-21907398

RESUMO

F.-Ulrich Hartl and Arthur Horwich will share this year's Lasker Basic Medical Science Award for the discovery of the cell's protein-folding machinery, exemplified by cage-like structures that convert newly synthesized proteins into their biologically active forms. Their fundamental findings reveal mechanisms that operate in normal physiologic processes and help to explain the problems that arise in diseases of protein folding.


Assuntos
Distinções e Prêmios , Biologia/história , Dobramento de Proteína , Proteínas/metabolismo , Animais , Escherichia coli/metabolismo , Proteínas de Choque Térmico HSP72/metabolismo , História do Século XX , Humanos , Modelos Moleculares , Chaperonas Moleculares/metabolismo , Proteínas/química , Estados Unidos
6.
J Hist Biol ; 57(2): 207-229, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38662180

RESUMO

The importance of naturalization-the establishment of species introduced into foreign places-to the early development of Darwin's theory of evolution deserves historical attention. Introduced and invasive European species presented Darwin with interpretive challenges during his service as naturalist on the HMS Beagle. Species naturalization and invasive species strained the geologist Charles Lyell's creationist view of the organic world, a view which Darwin adopted during the voyage of the Beagle but came to question afterward. I suggest that these phenomena primed Darwin to question the "stability of species." I then examine the role of introduced and invasive species in Darwin's early theorizing and negotiation with Lyell's ideas, recorded in his post-voyage "transmutation notebooks." Therein, the subject was an inflection point in his contention with Lyell's views and moreover, his theorizing on invasive species occasioned some of his earliest inklings of natural selection. Finally, I examine how naturalization was crucial to Lyell's own eventual conversion to evolutionism. I conclude with brief reflections on the implications of this narrative for our understanding of Darwin's reasoning, his intellectual relationship to Lyell, and the historical context that shaped his theory.


Assuntos
Evolução Biológica , Espécies Introduzidas , Seleção Genética , Espécies Introduzidas/história , História do Século XIX , Animais , Biologia/história , História Natural/história
8.
Hist Philos Life Sci ; 44(4): 54, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36326954

RESUMO

This paper examines the efforts in evolution research to understand form's structure that developed in Italy during the first half of the twentieth century. In particular, it analyzes how the organic approach in biology and the study of organic form merged in the morphological research agendas of Giuseppe Colosi (1892-1975) and Giuseppe Levi (1872-1965). These biologists sought to understand form's inner composition and structure. First, I will briefly outline the morphological practices and frameworks used to study form changes and structures in the early twentieth century. Second, I will discuss what the Italian biologist Antonio Pensa (1874-1970) called the morphological problem. Third, I will examine Colosi's response to the morphological problem. Fourth, I will analyze Levi's morphological research program. As a result, this paper paves the way for a more nuanced and varied picture of the so-called "organicism movement" in the first half of the twentieth century by calling attention to morphology as practiced in Italian-speaking biology. In fact, alongside dialectical materialism and holistic biology, two of the main strands within organicism, the architectural approach to evolution as practiced in Italy and elsewhere had a profound impact on twentieth- and twenty-first-century organicism specifically and on evolutionary biology generally.


Assuntos
Biologia , Idioma , História do Século XX , Itália , Biologia/história
9.
Hist Philos Life Sci ; 44(1): 10, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35258853

RESUMO

The rise of the mechanistic worldview in the seventeenth century had a major impact on views of biological generation. Many seventeenth century naturalists rejected the old animist thesis. However, the alternative view of gradual mechanistic formation in embryology didn't convince either. How to articulate the peculiarity of life? Researchers in the seventeenth century proposed both "animist" and mechanistic theories of life. In the eighteenth century again a controversy in biology arose regarding the explanation of generation. Some adhered to the view that life is a physical property of matter (e.g. Buffon), others saw living entities as the result of the development of pre-existing germs (e.g. Bonnet). Naturalists, lacked a convincing account that could guide their research. In interaction with leading naturalists of his time Immanuel Kant articulated an approach to explaining generation. Kant's account, delineated in his Kritik der Urteilskraft (Critique of the power of judgment) (1790), is a combination of Newtonian non-reductionist mechanism in explanation, and a concept of natural end comparable to Stahl's formal conception of organic bodies. It consists of two claims: a) in biology only mechanical explanation is explanatory, and b) living entities contain some original organisation, which is mechanically unexplainable. In the nineteenth century this approach influenced naturalists as Müller, Virchow, and Von Baer, in their physiological research. Dissatisfied with a sheer mechanistic or, on the other hand, a sheer teleological approach, they appreciated the Kantian account of mechanical explanation of natural ends. In Germany, in the second halve of the nineteenth century, Ernst Haeckel reopened the debate about abiogenesis, which still continuous.


Assuntos
Emoções , Julgamento , Biologia/história , Alemanha , História do Século XVIII , Filosofia/história
10.
Ber Wiss ; 45(3): 384-396, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36086844

RESUMO

In this paper, I ask about the broader context of the history and philosophy of biology in the German-speaking world as the place in which Hans-Jörg Rheinberger began his work. Three German philosophical traditions-neo-Kantianism, phenomenology, and Lebensphilosophie-were interested in the developments and conceptual challenges of the life sciences in the late nineteenth and early twentieth centuries. Their reflections were taken up by life scientists under the terms theoretische Biologie (theoretical biology) and allgemeine Biologie (general biology), i. e., for theoretical and methodological reflections. They used historical and philosophical perspectives to develop vitalistic, organicist, or holistic approaches to life. In my paper, I argue that the resulting discourse did not come to an end in 1945. Increasingly detached from biological research, it formed an important context for the formation of the field of history and philosophy of biology. In Rheinberger's work, we can see the "Spalten" and "Fugen"-the continuities and discontinuities-that this tradition left there.


Assuntos
Disciplinas das Ciências Biológicas , Filosofia , Disciplinas das Ciências Biológicas/história , Biologia/história , Filosofia/história , Vitalismo/história
11.
Ber Wiss ; 45(3): 397-414, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36086846

RESUMO

In this article, I first outline the professionalization of the history and philosophy of biology from the 1960s onward. Then, I attempt to situate the work of Hans-Jörg Rheinberger with respect to this field. On the one hand, Rheinberger was marginal with respect to Anglo-American philosophical tradition; on the other, he was very influential in building up an integrated history and philosophy of the life sciences community at the Max Planck Institute for the History of Science in Berlin and beyond. This marginality results, I suggest, from three main sources: his use of concepts coming from continental traditions in the study of the life sciences, which are foreign to Anglo-American philosophers of science; his focus on practices instead of theories; and his research trajectory as a molecular biologist, which led him to be critical of disciplinary boundaries. As a first step in situating and historicizing Rheinberger's trajectory, this article invites comparative studies and calls for a history of "continental philosophy of biology" in the twentieth century.


Assuntos
Disciplinas das Ciências Biológicas , Conhecimento , Disciplinas das Ciências Biológicas/história , Biologia/história , Internacionalidade , Filosofia/história , Estados Unidos
12.
Hist Philos Life Sci ; 43(2): 53, 2021 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-33835294

RESUMO

Thomas Henry Huxley and Charles Darwin discovered in 1857 that they had a fundamental disagreement about biological classification. Darwin believed that the natural system should express genealogy while Huxley insisted that classification must stand on its own basis, independent of evolution. Darwin used human races as a model for his view. This private and long-forgotten dispute exposes important divisions within Victorian biology. Huxley, trained in physiology and anatomy, was a professional biologist while Darwin was a gentleman naturalist. Huxley agreed with John Stuart Mill's rejection of William Whewell's sympathy for Linnaeus. The naturalists William Sharp Macleay, Hugh Strickland, and George Waterhouse worked to distinguish two kinds of relationship, affinity and analogy. Darwin believed that his theory could explain the difference. Richard Owen introduced the distinction between homology and analogy to anatomists, but the word homology did not enter Darwin's vocabulary until 1848, when he used the morphological concept of archetype in his work on Cirripedia. Huxley dropped the word archetype when Richard Owen linked it to Plato's ideal forms, replacing it with common plan. When Darwin wrote in the Origin of Species that the word plan gives no explanation, he may have had Huxley in mind. Darwin's preposterous story in the Origin about a bear giving birth to a kangaroo, which he dropped in the second edition, was in fact aimed at Huxley.


Assuntos
Evolução Biológica , Biologia/história , Dissidências e Disputas/história , História do Século XIX , História Natural/história
13.
Hist Philos Life Sci ; 43(2): 77, 2021 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-34081225

RESUMO

The biogeographic contributions of Léon Croizat (1894-1982) and the conflictive relationships with his intellectual descendants and critics are analysed. Croizat's panbiogeography assumed that vicariance is the most important biogeographic process and that dispersal does not contribute to biogeographic patterns. Dispersalist biogeographers criticized or avoided mentioning panbiogeography, especially in the context of the "hardening" of the Modern Synthesis. Researchers at the American Museum of Natural History associated panbiogeography with Hennig's phylogenetic systematics, creating cladistic biogeography. On the other hand, a group of New Zealand biologists formalized Croizat's original concepts and soon began arguing with cladistic biogeographers over the relative merits of their approaches. In Latin America, panbiogeography and cladistic biogeography were incorporated as parts of an integrative approach. A recent development, molecular panbiogeography, is based on the use of molecular phylogenetic data. The current practice shows that some authors insist on considering panbiogeography as the only appropriate approach and vicariance as the only relevant process, whereas others accept Croizat's dictum "Earth and life evolve together" as a useful guide to understanding broad, general patterns, but recognize that dispersal also contributes substantially to biotic assembly. The framework of integrative pluralism allows to explain the complexities of the biogeographic processes involved in biotic assembly without the need of unification on a large scale. This historical analysis intersects with the existing historiography of the Modern Synthesis and may provide some insights on the dynamics of integrative pluralism, which may be especially relevant in the current development of the Extended Synthesis.


Assuntos
Distribuição Animal , Biologia/história , Dispersão Vegetal , Biologia/métodos , Biologia/normas , História do Século XX , História do Século XXI
14.
Hist Philos Life Sci ; 43(3): 89, 2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34251537

RESUMO

We invite systematic consideration of the metaphors of cycles and circulation as a long-term theme in the history of the life and environmental sciences and medicine. Ubiquitous in ancient religious and philosophical traditions, especially in representing the seasons and the motions of celestial bodies, circles once symbolized perfection. Over the centuries cyclic images in western medicine, natural philosophy, natural history and eventually biology gained independence from cosmology and theology and came to depend less on strictly circular forms. As potent 'canonical icons', cycles also interacted with representations of linear and irreversible change, including arrows, arcs, scales, series and trees, as in theories of the Earth and of evolution. In modern times life cycles and reproductive cycles have often been held to characterize life, in some cases especially female life, while human efforts selectively to foster and disrupt these cycles have harnessed their productivity in medicine and agriculture. But strong cyclic metaphors have continued to link physiology and climatology, medicine and economics, and biology and manufacturing, notably through the relations between land, food and population. From the grand nineteenth-century transformations of matter to systems ecology, the circulation of molecules through organic and inorganic compartments has posed the problem of maintaining identity in the face of flux and highlights the seductive ability of cyclic schemes to imply closure where no original state was in fact restored. More concerted attention to cycles and circulation will enrich analyses of the power of metaphors to naturalize understandings of life and their shaping by practical interests and political imaginations.


Assuntos
Biologia/história , História da Medicina , Filosofia/história , História do Século XV , História do Século XVI , História do Século XVII , História do Século XVIII , História do Século XIX , História do Século XX , História do Século XXI , História Antiga , História Medieval
15.
J Bacteriol ; 202(23)2020 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-32958632

RESUMO

This minireview presents the career of biophysicist Howard Berg from his first interest in bacterial chemotaxis and motility through the present. After a summary of some of his early work, a series of reminiscences of students, postdocs, colleagues, and family members is presented. In sum, these recollections capture the effect that Howard's scientific life has had on the field of bacterial chemotaxis and motility and on the careers and lives of those who have interacted with him.


Assuntos
Biologia/história , Biofísica/história , Bactérias/química , Bactérias/citologia , Fenômenos Fisiológicos Bacterianos , Quimiotaxia , História do Século XX , Humanos
16.
PLoS Biol ; 15(9): e2003243, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28922352

RESUMO

In September 1957, Francis Crick gave a lecture in which he outlined key ideas about gene function, in particular what he called the central dogma. These ideas still frame how we understand life. This essay explores the concepts he developed in this influential lecture, including his prediction that we would study evolution by comparing sequences.


Assuntos
Biologia/história , Pessoas Famosas , Expressão Gênica , Evolução Biológica , História do Século XX
17.
Nat Rev Mol Cell Biol ; 9(3): 255-62, 2008 03.
Artigo em Inglês | MEDLINE | ID: mdl-18292780

RESUMO

Over the past two decades, molecular and cell biologists have made important progress in characterizing the components and compartments of the cell. New visualization methods have also revealed cellular dynamics. This has raised complex issues about the organization principles that underlie the emergence of coherent dynamical cell shapes and functions. Self-organization concepts that were first developed in chemistry and physics and then applied to various morphogenetic problems in biology over the past century are now beginning to be applied to the organization of the living cell.


Assuntos
Biologia , Fenômenos Fisiológicos Celulares , Animais , Evolução Biológica , Biologia/história , Forma Celular , Retroalimentação Fisiológica , História do Século XX , História do Século XXI , Humanos , Microtúbulos/metabolismo , Termodinâmica
18.
J Periodontal Res ; 55(6): 959-968, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32725852

RESUMO

Tony Melcher, a highly influential and forward-thinking scientist and teacher, focussed on the origins, behaviour and regulation of cells in periodontal tissues. His recent death in April 2020, has motivated us to highlight his multi-level contributions to research in biology and the dental sciences. Tony was particularly adept at recognizing the inherent instructive power of the periodontium, most notably as a model system for studying the inter-relationships between the structure, development and functions of connective tissues. Further, his mentoring of dozens of students who subsequently went on to develop their own careers in research, and his leadership in promoting collaborations in dental sciences world-wide, engendered important advances in the importance and utility of research relating to oral tissues. Here, we reflect upon his development of a large, multi-disciplinary research enterprise, the MRC Group in Periodontal Physiology at the University of Toronto and brief commentaries of those who worked with him there. We examine his early career development and then go on to consider some of his most highly cited publications and their impact on subsequent research trends.


Assuntos
Ligamento Periodontal , Periodonto , Regeneração , Biologia/história , Tecido Conjuntivo , História do Século XX , História do Século XXI , Humanos
20.
Hereditas ; 157(1): 48, 2020 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-33239087

RESUMO

BACKGROUND: The founders of Hereditas envisioned that race biology would be a major subject that had social applications with utmost importance in the near future. Anthropometrics was in this context understood to be the pure and eugenics the applied science. Sweden had a long tradition in physical anthropometry. Herman Lundborg, member of the advisory board of Hereditas, united the anthropometric and eugenic approaches in a synthesis. He was the first head of the Institute for Race Biology in Sweden. The contents of Hereditas reflect the development of race biology in the Nordic countries. CONCLUSIONS: The initial enthusiasm for applied race biology did not last long. In the 1920's Hereditas carried papers on both physical anthropology and eugenics. Most paper dealt, however, with human genetics without eugenic content. Two papers, published in 1921 and 1939 show how the intellectual climate had changed from positive to negative. Finally only human genetics prevailed as the legitimate study of the human race or humankind. A belated defense of eugenics published in 1951 did not help; geneticists had abandoned anthropometrics for good around the year 1940 and eugenics about a decade later. In spite of that, eugenic legislation was amended astonishingly late, in the 1970's. The development was essentially similar in all Nordic countries.


Assuntos
Biologia , Eugenia (Ciência) , Antropometria/métodos , Biologia/história , Biologia/métodos , Biologia/tendências , Cruzamento , Eugenia (Ciência)/história , Eugenia (Ciência)/métodos , Eugenia (Ciência)/tendências , Estudos de Associação Genética , Genética Populacional , História do Século XX , Genética Humana , Humanos , Melhoramento Vegetal , Grupos Raciais/genética , Países Escandinavos e Nórdicos
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