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- All Subjects: history
- All Subjects: Evolution (Biology)
- Creators: Creath, Richard
Description
Once perceived as an unimportant occurrence in living organisms, cell degeneration was reconfigured as an important biological phenomenon in development, aging, health, and diseases in the twentieth century. This dissertation tells a twentieth-century history of scientific investigations on cell degeneration, including cell death and aging. By describing four central developments in cell degeneration research with the four major chapters, I trace the emergence of the degenerating cell as a scientific object, describe the generations of a variety of concepts, interpretations and usages associated with cell death and aging, and analyze the transforming influences of the rising cell degeneration research. Particularly, the four chapters show how the changing scientific practices about cellular life in embryology, cell culture, aging research, and molecular biology of Caenorhabditis elegans shaped the interpretations about cell degeneration in the twentieth-century as life-shaping, limit-setting, complex, yet regulated. These events created and consolidated important concepts in life sciences such as programmed cell death, the Hayflick limit, apoptosis, and death genes. These cases also transformed the material and epistemic practices about the end of cellular life subsequently and led to the formations of new research communities. The four cases together show the ways cell degeneration became a shared subject between molecular cell biology, developmental biology, gerontology, oncology, and pathology of degenerative diseases. These practices and perspectives created a special kind of interconnectivity between different fields and led to a level of interdisciplinarity within cell degeneration research by the early 1990s.
ContributorsJiang, Lijing (Author) / Maienschein, Jane (Thesis advisor) / Laubichler, Manfred (Thesis advisor) / Hurlbut, James (Committee member) / Creath, Richard (Committee member) / White, Michael (Committee member) / Arizona State University (Publisher)
Created2013
Description
How fast is evolution? In this dissertation I document a profound change that occurred around the middle of the 20th century in the way that ecologists conceptualized the temporal and spatial scales of adaptive evolution, through the lens of British plant ecologist Anthony David Bradshaw (1926–2008). In the early 1960s, one prominent ecologist distinguished what he called “ecological time”—around ten generations—from “evolutionary time”— around half of a million years. For most ecologists working in the first half of the 20th century, evolution by natural selection was indeed a slow and plodding process, tangible in its products but not in its processes, and inconsequential for explaining most ecological phenomena. During the 1960s, however, many ecologists began to see evolution as potentially rapid and observable. Natural selection moved from the distant past—a remote explanans for both extant biological diversity and paleontological phenomena—to a measurable, quantifiable mechanism molding populations in real time.
The idea that adaptive evolution could be rapid and highly localized was a significant enabling condition for the emergence of ecological genetics in the second half of the 20th century. Most of what historians know about that conceptual shift and the rise of ecological genetics centers on the work of Oxford zoologist E. B. Ford and his students on polymorphism in Lepidotera, especially industrial melanism in Biston betularia. I argue that ecological genetics in Britain was not the brainchild of an infamous patriarch (Ford), but rather the outgrowth of a long tradition of pastureland research at plant breeding stations in Scotland and Wales, part of a discipline known as “genecology” or “experimental taxonomy.” Bradshaw’s investigative activities between 1948 and 1968 were an outgrowth of the specific brand of plant genecology practiced at the Welsh and Scottish Plant Breeding stations. Bradshaw generated evidence that plant populations with negligible reproductive isolation—separated by just a few meters—could diverge and adapt to contrasting environmental conditions in just a few generations. In Bradshaw’s research one can observe the crystallization of a new concept of rapid adaptive evolution, and the methodological and conceptual transformation of genecology into ecological genetics.
The idea that adaptive evolution could be rapid and highly localized was a significant enabling condition for the emergence of ecological genetics in the second half of the 20th century. Most of what historians know about that conceptual shift and the rise of ecological genetics centers on the work of Oxford zoologist E. B. Ford and his students on polymorphism in Lepidotera, especially industrial melanism in Biston betularia. I argue that ecological genetics in Britain was not the brainchild of an infamous patriarch (Ford), but rather the outgrowth of a long tradition of pastureland research at plant breeding stations in Scotland and Wales, part of a discipline known as “genecology” or “experimental taxonomy.” Bradshaw’s investigative activities between 1948 and 1968 were an outgrowth of the specific brand of plant genecology practiced at the Welsh and Scottish Plant Breeding stations. Bradshaw generated evidence that plant populations with negligible reproductive isolation—separated by just a few meters—could diverge and adapt to contrasting environmental conditions in just a few generations. In Bradshaw’s research one can observe the crystallization of a new concept of rapid adaptive evolution, and the methodological and conceptual transformation of genecology into ecological genetics.
ContributorsPeirson, Bruce Richard Erick (Author) / Laubichler, Manfred D (Thesis advisor) / Maienschein, Jane (Thesis advisor) / Creath, Richard (Committee member) / Collins, James (Committee member) / Arizona State University (Publisher)
Created2015
Description
The Modern Synthesis embodies a theory of natural selection where selection is to be fundamentally understood in terms of measures of fitness and the covariance of reproductive success and trait or character variables. Whether made explicit or left implicit, the notion that selection requires that some trait variable cause reproductive success has been deemphasized in our modern understanding of exactly what selection amounts to. The dissertation seeks to advance a theory of natural selection that is fundamentally causal. By focusing on the causal nature of natural selection (rather than on fitness or statistical formulae), certain conceptual and methodological problems are seen in a new, clarifying light and avenues toward new, interesting solutions to those problems are illustrated. First, the dissertation offers an update to explicitly causal theories of when exactly a trait counts as an adaptation upon fixation in a population and draws out theoretical and practical implications for evolutionary biology. Second, I examine a case of a novel character that evolves by niche construction and argue that it evolves by selection for it and consider implications for understanding adaptations and drift. The third contribution of the dissertation is an argument for the importance of defining group selection causally and an argument against model pluralism in the levels of selection debate. Fourth, the dissertation makes a methodological contribution. I offer the first steps toward an explicitly causal methodology for inferring the causes of selection—something often required in addition to inferring the causes of reproductive success. The concluding chapter summarizes the work and discusses potential paths for future work.
ContributorsAnderson, Wesley (Author) / Armendt, Brad (Thesis advisor) / Creath, Richard (Committee member) / Glymour, Bruce (Committee member) / Kinzig, Ann (Committee member) / Perrings, Charles (Committee member) / Arizona State University (Publisher)
Created2016
Description
The study of wasp societies (family Vespidae) has played a central role in advancing our knowledge of why social life evolves and how it functions. This dissertation asks: How have scientists generated and evaluated new concepts and theories about social life and its evolution by investigating wasp societies? It addresses this question both from a narrative/historical and from a reflective/epistemological perspective. The historical narratives reconstruct the investigative pathways of the Italian entomologist Leo Pardi (1915-1990) and the British evolutionary biologist William D. Hamilton (1936-2000). The works of these two scientists represent respectively the beginning of our current understanding of immediate and evolutionary causes of social life. Chapter 1 shows how Pardi, in the 1940s, generated a conceptual framework to explain how wasp colonies function in terms of social and reproductive dominance. Chapter 2 shows how Hamilton, in the 1960s, attempted to evaluate his own theory of inclusive fitness by investigating social wasps. The epistemological reflections revolve around the idea of investigative framework for theory evaluation. Chapter 3 draws on the analysis of important studies on social wasps from the 1960s and 1970s and provides an account of theory evaluation in the form of an investigative framework. The framework shows how inferences from empirical data (bottom-up) and inferences from the theory (top-down) inform one another in the generation of hypotheses, predictions and statements about phenomena of social evolution. It provides an alternative to existing philosophical accounts of scientific inquiry and theory evaluation, which keep a strong, hierarchical distinction between inferences from the theory and inferences from the data. The historical narratives in this dissertation show that important scientists have advanced our knowledge of complex biological phenomena by constantly interweaving empirical, conceptual, and theoretical work. The epistemological reflections argue that we need holistic frameworks that account for how multiple scientific practices synergistically contribute to advance our knowledge of complex phenomena. Both narratives and reflections aim to inspire and inform future work in social evolution capitalizing on lessons learnt from the past.
ContributorsCaniglia, Guido (Author) / Laubichler, Manfred (Thesis advisor) / Maienschein, Jane (Thesis advisor) / Creath, Richard (Committee member) / Mitchell, Sandra (Committee member) / Arizona State University (Publisher)
Created2016
Description
A central task for historians and philosophers of science is to characterize and analyze the epistemic practices in a given science. The epistemic practice of a science includes its explanatory goals as well as the methods used to achieve these goals. This dissertation addresses the epistemic practices in gene expression research spanning the mid-twentieth century to the twenty-first century. The critical evaluation of the standard historical narratives of the molecular life sciences clarifies certain philosophical problems with respect to reduction, emergence, and representation, and offers new ways with which to think about the development of scientific research and the nature of scientific change.
The first chapter revisits some of the key experiments that contributed to the development of the repression model of genetic regulation in the lac operon and concludes that the early research on gene expression and genetic regulation depict an iterative and integrative process, which was neither reductionist nor holist. In doing so, it challenges a common application of a conceptual framework in the history of biology and offers an alternative framework. The second chapter argues that the concept of emergence in the history and philosophy of biology is too ambiguous to account for the current research in post-genomic molecular biology and it is often erroneously used to argue against some reductionist theses. The third chapter investigates the use of network representations of gene expression in developmental evolution research and takes up some of the conceptual and methodological problems it has generated. The concluding comments present potential avenues for future research arising from each substantial chapter.
In sum, this dissertation argues that the epistemic practices of gene expression research are an iterative and integrative process, which produces theoretical representations of the complex interactions in gene expression as networks. Moreover, conceptualizing these interactions as networks constrains empirical research strategies by the limited number of ways in which gene expression can be controlled through general rules of network interactions. Making these strategies explicit helps to clarify how they can explain the dynamic and adaptive features of genomes.
The first chapter revisits some of the key experiments that contributed to the development of the repression model of genetic regulation in the lac operon and concludes that the early research on gene expression and genetic regulation depict an iterative and integrative process, which was neither reductionist nor holist. In doing so, it challenges a common application of a conceptual framework in the history of biology and offers an alternative framework. The second chapter argues that the concept of emergence in the history and philosophy of biology is too ambiguous to account for the current research in post-genomic molecular biology and it is often erroneously used to argue against some reductionist theses. The third chapter investigates the use of network representations of gene expression in developmental evolution research and takes up some of the conceptual and methodological problems it has generated. The concluding comments present potential avenues for future research arising from each substantial chapter.
In sum, this dissertation argues that the epistemic practices of gene expression research are an iterative and integrative process, which produces theoretical representations of the complex interactions in gene expression as networks. Moreover, conceptualizing these interactions as networks constrains empirical research strategies by the limited number of ways in which gene expression can be controlled through general rules of network interactions. Making these strategies explicit helps to clarify how they can explain the dynamic and adaptive features of genomes.
ContributorsRacine, Valerie (Author) / Maienschein, Jane (Thesis advisor) / Laubichler, Manfred D (Thesis advisor) / Creath, Richard (Committee member) / Newfeld, Stuart (Committee member) / Morange, Michel (Committee member) / Arizona State University (Publisher)
Created2016
Description
This dissertation examines the efforts of the Carnegie Image Tube Committee (CITC), a group created by Vannevar Bush and composed of astronomers and physicists, who sought to develop a photoelectric imaging device, generally called an image tube, to aid astronomical observations. The Carnegie Institution of Washington’s Department of Terrestrial Magnetism coordinated the CITC, but the committee included members from observatories and laboratories across the United States. The CITC, which operated from 1954 to 1976, sought to replace direct photography as the primary means of astronomical imaging.
Physicists, who gained training in electronics during World War II, led the early push for the development of image tubes in astronomy. Vannevar Bush’s concern for scientific prestige led him to form a committee to investigate image tube technology, and postwar federal funding for the sciences helped the CITC sustain development efforts for a decade. During those development years, the CITC acted as a mediator between the astronomical community and the image tube producers but failed to engage astronomers concerning various development paths, resulting in a user group without real buy-in on the final product.
After a decade of development efforts, the CITC designed an image tube, which Radio Corporation of American manufactured, and, with additional funding from the National Science Foundation, the committee distributed to observatories around the world. While excited about the potential of electronic imaging, few astronomers used the Carnegie-developed device regularly. Although the CITC’s efforts did not result in an overwhelming adoption of image tubes by the astronomical community, examining the design, funding, production, and marketing of the Carnegie image tube shows the many and varied processes through which astronomers have acquired new tools. Astronomers’ use of the Carnegie image tube to acquire useful scientific data illustrates factors that contribute to astronomers’ adoption or non-adoption of those new tools.
Physicists, who gained training in electronics during World War II, led the early push for the development of image tubes in astronomy. Vannevar Bush’s concern for scientific prestige led him to form a committee to investigate image tube technology, and postwar federal funding for the sciences helped the CITC sustain development efforts for a decade. During those development years, the CITC acted as a mediator between the astronomical community and the image tube producers but failed to engage astronomers concerning various development paths, resulting in a user group without real buy-in on the final product.
After a decade of development efforts, the CITC designed an image tube, which Radio Corporation of American manufactured, and, with additional funding from the National Science Foundation, the committee distributed to observatories around the world. While excited about the potential of electronic imaging, few astronomers used the Carnegie-developed device regularly. Although the CITC’s efforts did not result in an overwhelming adoption of image tubes by the astronomical community, examining the design, funding, production, and marketing of the Carnegie image tube shows the many and varied processes through which astronomers have acquired new tools. Astronomers’ use of the Carnegie image tube to acquire useful scientific data illustrates factors that contribute to astronomers’ adoption or non-adoption of those new tools.
ContributorsThompson, Samantha Michelle (Author) / Ellison, Karin (Thesis advisor) / Wetmore, Jameson (Thesis advisor) / Maienschein, Jane (Committee member) / Creath, Richard (Committee member) / DeVorkin, David (Committee member) / Arizona State University (Publisher)
Created2019
Description
This dissertation is an historical analysis of the science of human origins, paleoanthropology, examining the intersection of science and culture around fossil human ancestors (hominins) over the last century and a half. Focusing on fossils as scientific objects, this work examines three controversial fossils from the science’s history asking, how do fossils formulate, challenge, and reconfigure notions of what it means to be human? The introduction reviews the historiography of paleoanthropology and the gaps that exist in the literature. Chapter two examines the first case study, the type specimen of Homo neanderthalensis, known as the Feldhofer Neanderthal, providing a biography of the object from its discovery in Germany in 1856 until its species designation in 1864. Chapter three briefly links the Neanderthal’s story in time and space to the next fossil’s story. Chapter four picks up the story of paleoanthropology in 1924 in South Africa, with the discovery and initial analysis of a specimen nicknamed the Taungs Baby, which was labeled a new hominin species, Australopithecus africanus. Chapter five is another brief chapter connecting the Taungs Baby story in time and space to the final specimen examined in this work at the end of the century. Chapter six examines the final case study, a specimen discovered in 2003 in Indonesia, designated a new species named Homo floresiensis and nicknamed the Hobbit. Through comparing contrasting, and connecting the stories of these three specimens, three major conclusions emerge about the field. First, the fossils themselves play an important role in knowledge production about the hominin past. Second, scientific practice shaped both interpretations of fossils and larger questions of what it means to be human. Third, the scientific practice is itself shaped by local culture, which continually interacts with attempts to establish a global perspective about the human past. The perspective gleaned through the eyes of these three fossils therefore reveals the way shifting, rather than eternally true, claims are embedded in culture and intertwined with the perspectives of the humans conducting the science.
ContributorsMadison, Paige (Author) / Maienschein, Jane (Thesis advisor) / Kimbel, William (Committee member) / Creath, Richard (Committee member) / Hurlbut, James (Committee member) / Laubichler, Mandred (Committee member) / Arizona State University (Publisher)
Created2020