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1.
Henry Hurd Rusby (1855–1940) is one of the outstanding personalities in the history of the New York Botanical Garden (NYBG). He played a significant role, not only in the founding of NYBG in 1891, but also in establishing a strong precedent of research and exploration in the field of economic botany at the new institution. As a result of Rusby’s influence and activity, the study of useful plants formed an important part of NYBG’s original mandate, an institutional commitment that was rejuvenated nearly a century later, with the formation of the Institute of Economic Botany. An indefatigable researcher both in the field and in the herbarium, Rusby left behind a voluminous corpus of published work in systematic and economic botany that is a legacy for modern botanists and pharmacologists.  相似文献   

2.
It’s recently been argued that biological fitness can’t change over the course of an organism’s life as a result of organisms’ behaviors. However, some characterizations of biological function and biological altruism tacitly or explicitly assume that an effect of a trait can change an organism’s fitness. In the first part of the paper, I explain that the core idea of changing fitness can be understood in terms of conditional probabilities defined over sequences of events in an organism’s life. The result is a notion of “conditional fitness” which is static but which captures intuitions about apparent behavioral effects on fitness. The second part of the paper investigates the possibility of providing a systematic foundation for conditional fitness in terms of spaces of sequences of states of an organism and its environment. I argue that the resulting “organism–environment history conception” helps unify diverse biological perspectives, and may provide part of a metaphysics of natural selection.
Marshall AbramsEmail:
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3.
The spread of alien plant species is a critical ecological event worldwide, but the forces that control this spread are not well documented. Alien plant species are well known to disrupt ecological services of native ecosystems, change the composition of native habitats, and often lead to the extirpation of native flora and fauna. Here, we report on life history patterns of plant species with rapidly spreading and declining ranges in North America’s major urban region. We tested for differences in life history traits between the 466 native and alien woody flora of the New York metropolitan area. We also examined the relationship between life history traits and change in distribution in the New York metropolitan area between 1900 and 2000. Native and alien species of the New York metropolitan area differ with respect to pollination vector and breeding system. However, pollination vector and breeding system are not associated with success, defined here as increasing range spread in the urban environment; instead, fruit type (dispersal), life form and origin are important determinants of success. Alien species that are deciduous trees, shrubs or vines with fleshy fruit are the most successful in increasing their distribution in this urban landscape. Newly introduced species with these characteristics are expected to have a better chance at establishing in similar urban landscapes and should be targets for intensive management. The ability to predict which alien species will become invasive is also a valuable tool for the prevention of invasions by newly introduced plant species.  相似文献   

4.
I argue that the metaphysical capacity of autonomy is not intrinsically valuable; it is valuable only when used in relation to a community's values and instrumentally for making the proper choices that will promote one's own and the community's well‐being. I use the example of the choice to take one's life by suicide to illuminate this view. I articulate a plausible African conception of personhood as a basis for the idea of relational autonomy. I argue that this conception is better understood as a social‐moral thesis, and not a metaphysical thesis. A metaphysical thesis gives an account of the abstract nature of an atomic individual, his agency, and rational choice. The social‐moral thesis indicates that personhood and autonomy are positive and relational to the life plans, well‐being, material conditions, and the best means for achieving them that are made available and possible by harmonious living in a community. This idea of autonomy is not just having the capacity of freewill; it also involves how such freewill is used, in terms of how an individual's choices are guided by internalized communal values.  相似文献   

5.
The enslavement of Africans, which gave birth to the African Diaspora in the Atlantic world, scattered people who shared the same cultural and linguistic affinity but often lumped them together in identifiable regional patterns. A significant consequence of the pattern of trade was the emergence of identifiable “ethnic” and cultural patterns in the diaspora. Attention, therefore, has for a long time focused on the pattern of dispersion and the impact of the Atlantic slave trade on the emergence of New World cultures. This paper addresses what I call the “question of Igbo history, ethnicity and identity,” with a view to presenting a synthesis and a framework for understanding the essence of ndiIgbo as flexible in both Africa and the Atlantic Diaspora. The case of the Igbo suggests that identities are multi-layered, self imposed, as well as ascribed by others and as such require a critical analysis to avoid the essentialism that have bedeviled much of the discourse on African identity in the diaspora  相似文献   

6.
Ezenwa-Ohaeto’s life encapsulates what the critic and novelist Isidore Okpewho has described as the “dignity of intellectual labour.” This becomes clear as we take into consideration, the range of his production as a poet, scholar, and occasional journalist. Ezenwa-Ohaeto’s work grapples with a vast range of areas of specifically Nigerian literature and culture in the 20th century, but in general with the literature of the postcolonial world as they have come to express distinct, recognizable moral and aesthetic values. His untimely death in 2005 therefore, has implication for the study of this literature, particularly because it marks the closure of the questic imagination of a poet/scholar whose interventions were critical in the formation of the critical values of contemporary African writing. This paper examines Ezenwa-Ohaeto’s contributions in the light of this, and puts in some perspective, aspects of his life and work, and its implications in the formal canon that he helped to shape and stabilize.  相似文献   

7.
Julius Schaxel is an almost forgotten figure in the history of early twentieth century biology. By focusing on his life and work, I would like to illustrate several central developments in that period of history of biology. Julius Schaxel was an early representative and organizer of theoretical biology, discussing and criticizing both Wilhelm Roux’s mechanism and Hans Driesch’s vitalism. In addition to his theoretical work, Schaxel also did experimental research on developmental issues to support his critique. In this paper, special emphasis is made on the negotiating practice of Schaxel, which he used to establish a new area of biological research and a new audience for that area. In contrast to these new fields, Schaxel can be also portrayed as the endpoint of a research tradition investigating ontogeny and phylogeny together, which today is called Evo–Devo. Following Garland Allen’s dialectical processes that led to the decline of the Evo–Devo research agenda, Schaxel’s example is used to investigate these processes.  相似文献   

8.
This article will argue that the differences between art history and the anthropology of art not just due to discipline-driven methodologies, though these are certainly a factor, but also occur because art historians and anthropologists are usually asking rather different questions, and finding the answers in quite different places within the culture. As a starting point I will demonstrate these differences of both approach and result, using two acclaimed studies by anthropologists of African expressive culture, one from the Congo (Zaïre), the other from Sierra Leone. Although very different from each other, both downplay the importance of affect, and both assume aesthetic practice is transparent, i.e. that it directly reflects the meaning of life or human behavior. No art historian would make such a confident assumption.  相似文献   

9.
From the viewpoint of 2007, one can trace the history of an interesting and contentious trend in biogeography and evolution that began with Croizat’s concept of panbiogeography in 1958. After a quiescent period of about 16 years, some young biologists in New York and in New Zealand read Croizat’s books and became enthusiastic supporters of his ideas. In New York, in the early 1970s, panbiogeography was combined with a part of Hennig’s phylogenetic method to create vicariance biogeography. In 1986, the name of the latter was changed to cladistic biogeography. In the meantime, Croizat’s followers in New Zealand sought to maintain panbiogeography in its original form without reference to phylogeny. This idea reached its peak of popularity in 1989–1990 and then began to fade. In comparison, cladistic biogeography became much more widespread, especially when its followers began publishing laudatory books and papers. Its decline became noticeable after the turn of the century as the dispersal counterrevolution began to have its effect. It served a useful purpose by engaging the interest of young biologists who otherwise may not have become aware of biogeography.  相似文献   

10.
We used mitochondrial DNA sequence comparisons to assess range-wide population structure and historical patterns of differentiation among populations of the bog turtle (Glyptemys muhlenbergii). This species is one of North America’s smallest and most endangered pond turtles, and is currently found in three largely disjunct groups of populations: in the southern U.S., in the northeast, and in the Finger Lakes and Lake Ontario Plains region of western and central New York State. All the New York sites and most of the northeastern sites were glaciated during the Pleistocene. We surveyed 2793 bases pairs of mitochondrial DNA spanning three genes (cytb, nd4, and d-loop) in 41 individuals from 21 populations throughout most of the bog turtle’s distribution. We found surprisingly low levels of divergence among populations, even in southern populations that have been hypothesized as refugia during times of climate change. Our data suggest populations of bog turtle’s suffered a bottleneck, followed by a rapid post-Pleistocene expansion into northern segments of the species’ range. We discuss historical changes in habitat availability and climate that may have influenced the historical deployment of lineages in this species, and possible life history traits and habitat dynamics that might also contribute to the overall low genetic diversity across its range.  相似文献   

11.
The comparison between United States immigrant and African‐American families presented by Daniel Patrick Moynihan in his 1965 report to President Lyndon Johnson remains the most popular folk model for explaining success, failure and mutual aid in poverty. Despite being savaged by social science in its first two decades and largely ignored in the last two, the Moynihan model is an enduring part of popular discourses on race, intensified by contemporary immigrant success narratives. Based on over three years of participant observation research among homeless African‐American and Latino men and their families and Latin‐American immigrants engaging in small business creation in New York City, I argue that Moynihan's empirically valid claim that certain immigrant family forms are more suited to mutual aid in crisis is misused to present the African‐American family as dysfunctional when its kinship norms are actually typically American.  相似文献   

12.
In 1749, Linnaeus presided over the dissertation “Oeconomia Naturae,” which argued that each creature plays an important and particular role in nature’s economy. This phrase should be familiar to readers of Darwin, for he claims in the Origin that “all organic beings are striving, it may be said, to seize on each place in the economy of nature.” Many scholars have discussed the influence of political economy on Darwin’s ideas. In this paper, I take a different tack, showing that Darwin’s idea of an economy of nature stemmed from the views of earlier naturalists like Linnaeus and Lyell. I argue, in the first section of the paper, that Linnaeus’ idea of oeconomia naturae is derived from the idea of the animal economy, and that his idea of politia naturae is an extension of the idea of a politia civitatis. In the second part, I explore the use of the concept of stations in the work of De Candolle and Lyell – the precursor to Darwin’s concept of places. I show in the third part of the paper that the idea of places in an economy of nature is employed by Darwin at many key points in his thinking: his discussion of the Galapagos birds, his reading of Malthus, etc. Finally, in the last section, I demonstrate that the idea of a place in nature’s economy is essential to Darwin’s account of divergence. To tell his famous story of divergence and adaptation, Darwin needed the economy of nature.  相似文献   

13.
In his 1987 book Controlling Life: Jacques Loeb and the Engineering Ideal in Biology, Philip Pauly presented his readers with the biologist Jacques Loeb and his role in developing an emphasis on control of life processes. Loeb’s work on artificial parthenogenesis, for example, provided an example of bioengineering at work. This paper revisits Pauly’s study of Loeb and explores the way current research in regenerative medicine reflects the same tradition. A history of regeneration research reveals patterns of thinking and research methods that both echo Loeb’s ideology and point the way to modern studies. Pauly’s work revealed far more than we readers realized at the time of its publication.  相似文献   

14.
William Bateson (1861–1926) has long occupied a controversial role in the history of biology at the turn of the twentieth century. For the most part, Bateson has been situated as the British translator of Mendel or as the outspoken antagonist of W.␣F. R. Weldon and Karl Pearson’s biometrics program. Less has been made of Bateson’s transition from embryologist to advocate for discontinuous variation, and the precise role of British and American influences in that transition, in the years leading up to the publication of his massive Materials for the Study of Variation (1894). In this paper, I first attempt to trace Bateson’s development in his early career before turning to search for the development of the moniker “anti-Darwinist” that has been attached to Bateson in well-known histories of the neo-Darwinian Synthesis.  相似文献   

15.
In the history of zoology the English anatomist Morrison Watson (1845–1885) is considered to be the discoverer of the masculinized sexual organs of the spotted hyena. Beginning in 1877, Watson had published a series of anatomical studies on the spotted hyena (Watson, 1877, 1878, 1881, Watson and Young, 1879), in which he, in which he for the first time made public the anatomical peculiarities of the female spotted hyena’s genitalia. This scientific achievement is well documented. But now we can also state that a hundred years before Watson the Dutch amateur zoologist Robert Jacob Gordon (1743–1795), while serving in the Scots Brigades at the Cape of Good Hope, had already made the same discovery and merely unfortunate personal circumstances prevented publication. During his stay at the Cape, Gordon had studied spotted hyenas intensively and recorded his observations in accurate drawings and comments. These drawings have been preserved as part of a large collection of animal drawings entitled Gordon Atlas. With his discovery, Gordon actually was the first to provide empirical evidence of a “curious and inexplicable case of dimorphism” (Darwin on a beetle) in mammalians, long before étienne Geoffrey Saint-Hilaire (Cours de l’histoire naturelle des mammifères, 1829) started examining masculinized sexual organs in the mole or Darwin recognized the importance of sexual dimorphism (Descent of Man, 1871). In this paper we reproduce for the first time all hyena drawings from the Gordon Atlas, including Gordon’s handwritten notes in the margins in the original Dutch and in translation. Additionally, we briefly delineate the knowledge about the South African spotted hyena in Gordon’s time and indicate that we doubt Watson’s explanation for the age-old confusion about the hyena.  相似文献   

16.
Interviewing offers the biographer unique opportunities for gathering data. I offer three examples. The emphatic bacterial geneticist Norton Zinder confronted me with an interpretation of Barbara McClintock’s science that was as surprising as it proved to be robust. The relaxed setting of the human geneticist Walter Nance’s rural summer home contributed to an unusually improvisational oral history that produced insights into his experimental and thinking style. And “embedding” myself with the biochemical geneticist Charles Scriver in his home, workplace, and city enabled me to experience the social networks that drive the practical events of his career, which in turn helped me explain the theoretical basis of his science. Face-to-face interaction and multisensory experience will shape each biographer’s experience uniquely. Recent developments in sensory physiology suggest that the experience of integrating sense data encourages different patterns of observation and reflection. It is reasonable, then, to think that biography based on face-to-face interviews will, for a given author, have a different character than one based entirely on documents. I reflect on how interviewing shapes my own writing and I encourage the reader to do the same.  相似文献   

17.
18.
In 1920, Eugen Steinach and Paul Kammerer reported experiments showing that exposure to high temperatures altered the structure of the gonad and produced hyper-sexuality in “heat rats,” presumably as a result of the increased production of sex hormones. Using Steinach’s evidence that the gonad is a double gland with distinct sexual and generative functions, they used their findings to explain “racial” differences in the sexuality of indigenous tropical peoples and Europeans. The authors also reported that heat induced anatomical changes in the interstitial cells of the gonad were inherited by the heat rats’ descendants. Kammerer used this finding to link endocrinology to his long-standing interest in the inheritance of acquired characteristics. The heat rats supported his hypothesis that the interstitial cells of the double gland were the mechanism of somatic induction in the inheritance of acquired characteristics. The Steinach–Kammerer collaboration, Kammerer’s use of Steinach’s “puberty gland” to explain somatic induction, and his endocrine analysis of symbiosis reveal Paul Kammerer’s late career attempt to integrate endocrinology and genetics with the political ideals of Austrian socialism. With them he developed a bioethics that challenged the growing reliance on race in eugenics and instead promoted cooperation over competition in evolution. I relate his attempt to the controversies surrounding the interstitial cells, to the status of extra-nuclear theories of heredity, and to Kammerer’s commitment to Austromarxist social reforms during the interwar period. I am very grateful for the help of several archivists, including Valerie-Ann Lutz, Roy Goodman and Robert Cox at the American Philosophical Society Library, Arlene Shaner at the New York Academy of Medicine, Shawn Wilson at the Kinsey Institute Library, the staff at the Archives of the University of Vienna, and Yukiko Sakabe at the Austrian Academy of Sciences. Thanks are also due to Andreas Lixl, who gave very helpful advice on German language and to many colleagues, including three anonymous reviewers, Paul Silvia, Alyce Miller, and the late Gilbert Gottlieb, who provided valuable comments as readers of earlier drafts. My discussions with Veronika Hofer have been especially rewarding. The research was funded by National Science Foundation grant #0240151.  相似文献   

19.
20.
A statistical analysis of strong and weak hydrogen bonds in the minor groove of DNA was carried out for a set of 70 drug-DNA complexes. The terms ‘strong’ and ‘weak’ pertain to the inherent strengths and weakness of the donor and acceptor fragments rather than to any energy considerations. The dataset was extracted from the protein data bank (PDB). The analysis was performed with an in-house software, hydrogen bond analysis tool (HBAT). In addition to strong hydrogen bonds such as O—H⋯O and N—H⋯O, the ubiquitous presence of weak hydrogen bonds such as C—H⋯O is implicated in molecular recognition. On an average, there are 1.4 weak hydrogen bonds for every strong hydrogen bond. For both categories of interaction, the N(3) of purine and the O(2) of pyrimidine are favoured acceptors. Donor multifurcation is common with the donors generally present in the drug molecules, and shared by hydrogen bond acceptors in the minor groove. Bifurcation and trifurcation are most commonly observed. The metrics for strong hydrogen bonds are consistent with established trends. The geometries are variable for weak hydrogen bonds. A database of recognition geometries for 26 literature amidinium-based inhibitors of Human African Trypanosomes (HAT) was generated with a docking study using seven inhibitors which occur in published crystal structures included in the list of 70 complexes mentioned above, and 19 inhibitors for which the drug-DNA complex crystal structures are unknown. The virtual geometries so generated correlate well with published activities for these 26 inhibitors, justifying our assumption that strong and weak hydrogen bonds are optimized in the active site.  相似文献   

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