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1.
Historians of science have attributed the emergence of ecology as a discipline in the late nineteenth century to the synthesis of Humboldtian botanical geography and Darwinian evolution. In this essay, I begin to explore another, largely neglected but very important dimension of this history. Using Sergei Vinogradskii’s career and scientific research trajectory as a point of entry, I illustrate the manner in which microbiologists, chemists, botanists, and plant physiologists inscribed the concept of a “cycle of life” into their investigations. Their research transformed a longstanding notion into the fundamental approaches and concepts that underlay the new ecological disciplines that emerged in the 1920s. Pasteur thus joins Humboldt as a foundational figure in ecological thinking, and the broader picture that emerges of the history of ecology explains some otherwise puzzling features of that discipline – such as its fusion of experimental and natural historical methodologies. Vinogradskii’s personal “cycle of life” is also interesting as an example of the interplay between Russian and Western European scientific networks and intellectual traditions. Trained in Russia to investigate nature as a super-organism comprised of circulating energy, matter, and life; over the course of five decades – in contact with scientists and scientific discourses in France, Germany, and Switzerland – he developed a series of research methods that translated the concept of a “cycle of life” into an ecologically conceived soil science and microbiology in the 1920s and 1930s. These methods, bolstered by his authority as a founding father of microbiology, captured the attention of an international network of scientists. Vinogradskii’s conceptualization of the “cycle of life” as chemosynthesis, autotrophy, and global nutrient cycles attracted the attention of ecosystem ecologists; and his methods appealed to practitioners at agricultural experiment stations and microbiological institutes in the United States, Western Europe, and the Soviet Union.  相似文献   

2.
Umbilical cord blood banking is one of many biomedical innovations that confront pregnant women with new choices about what they should do to secure their own and their child’s best interests. Many mothers can now choose to donate their baby’s umbilical cord blood (UCB) to a public cord blood bank or pay to store it in a private cord blood bank. Donation to a public bank is widely regarded as an altruistic act of civic responsibility. Paying to store UCB may be regarded as a “unique opportunity” to provide “insurance” for the child’s future. This paper reports findings from a survey of Australian women that investigated the decision to either donate or store UCB. We conclude that mothers are faced with competing discourses that force them to choose between being a “good mother” and fulfilling their role as a “good citizen.” We discuss this finding with reference to the concept of value pluralism.  相似文献   

3.
Seventy-five years ago, the geneticist Richard Goldschmidt hypothesized that single mutations affecting development could result in major phenotypic changes in a single generation to produce unique organisms within animal populations that he called “hopeful monsters”. Three decades ago, Sarah P. Gibbs proposed that photosynthetic unicellular micro-organisms like euglenoids and dinoflagellates are the products of a process now called “secondary endosymbiosis” (i.e., the evolution of a chloroplast surrounded by three or four membranes resulting from the incorporation of a eukaryotic alga by a eukaryotic heterotrophic host cell). In this article, we explore the evidence for Goldschmidt’s “hopeful monster” concept and expand the scope of this theory to include the macroevolutionary emergence of organisms like Euglena and Chlorarachnion from secondary endosymbiotic events. We argue that a Neo-Goldschmidtian perspective leads to the conclusion that cell chimeras such as euglenids and dinoflagellates, which are important groups of phytoplankton in freshwater and marine ecosystems, should be interpreted as “successful monsters”. In addition, we argue that Charles Darwin had euglenoids (infusoria) in mind when he speculated on the “primordial intermediate form”, although his Proto-Euglena-hypothesis for the origin of the last common ancestor of all forms of life is no longer acceptable.  相似文献   

4.
I review George Levine’s provocative and highly original book Darwin Loves You. Levine, whose “home discipline” is English Literature, offers a compelling interpretation of Darwin’s works, evaluating their content and Darwin’s prose style to identify a distinctly Darwinian attitude toward nature as a source of meaning and value. Levine believes that Darwin exemplifies the capacity to feel “enchantment” about the natural world, suggesting that, if Darwin’s example were followed, a “Darwinian re-enchantment of the world” would be brought about. This would offer a secular, non-supernatural basis for purpose, meaning, and value. I conclude with a few critical remarks about the scope and cogency of Levine’s proposal.  相似文献   

5.
In recent decades conservation biology has achieved a high position among the sciences. This is certainly true of South Africa, a small country, but the third most biodiverse in the world. This article traces some aspects of the transformation of South African wildlife management during the 1930s to the 1960s from game reserves based on custodianship and the “balance of nature” into scientifically managed national parks with a philosophy of “command and control” or “management by intervention.” In 1910 the four British colonies had formed the Union of South Africa, and by the 1920s there was wide acceptance of national parks, a development influenced by their success in the United States. It was not, however, until after the Second World War, that management of the expanding conservation estate altered from a rather unsystematic laissez faire variety, into more scientifically informed management practices with an efficient bureaucracy in charge. This was achieved by modifications in organizational structures and institutional cultures initiated by a change of government in 1948 which, this article argues, impacted in turn on wildlife management and shaped and professionalized many aspects of that field science. “Management by intervention” was the hallmark of South African wildlife and conservation biology from the 1960s until recently, when there have been shifts towards “adaptive resource management” in a period of further change in the country’s politics.  相似文献   

6.
Historians of science have only just begun to sample the wealth of different approaches to the study of animal behavior undertaken in the twentieth century. To date, more attention has been given to Lorenzian ethology and American behaviorism than to other work and traditions, but different approaches are equally worthy of the historian’s attention, reflecting not only the broader range of questions that could be asked about animal behavior and the “animal mind” but also the different contexts in which these questions were important. One such approach is that represented by the work of the French zoologist Louis Boutan (1859–1934). This paper explores the intellectual and cultural history of Boutan’s work on animal language and the animal mind, and contextualizes the place of animal behavior studies within late-nineteenth-and early-twentieth-century French biology. I explore the ways in which Boutan addressed the philosophical issue of whether language was necessary for abstract thought and show how he shifted from the idea that animals were endowed with a purely affective language to the notion that of they were capable of “rudimentary” reasoning. I argue that the scientific and broader socio-cultural contexts in which Boutan operated played a role in this transition. Then I show how Boutan’s linguistic and psychological experiments with a gibbon and children provide insights into his conception of “naturalness.” Although Boutan reared his gibbon at home and studied it in the controlled environment of his laboratory, he continued to identify its behavior as “natural.” I specifically demonstrate the importance of the milieu of the French Third Republic in shaping Boutan’s understanding not only of animal intelligence and child education, but also his definition of nature. Finally, I argue that Boutan’s studies on the primate mind provide us with a lens through which we can examine the co-invention of animal and child psychology in early-twentieth-century France.  相似文献   

7.
Summary In this paper we analyze Carl Gegenbaur’s conception of the relationship between embryology (“Ontogenie”) and comparative anatomy and his related ideas about homology. We argue that Gegenbaur’s conviction of the primacy of comparative anatomy and his careful consideration of caenogenesis led him to a more balanced view about the relationship between ontogeny and phylogeny than his good friend Ernst Haeckel. We also argue that Gegenbaur’s ideas about the centrality of comparative anatomy and his definitions of homology actually laid the conceptual foundations for Hans Spemann’s (1915) later analysis of homology. We also analyze Gegenbaur’s reception in the United States and how the discussions between E.B. Wilson and Edwin Conklin about the role of the “embryological criterion of homology” and the latter’s argument for an even earlier concept of cellular homology reflect the recurring theme of preformism in ontogeny, a theme that finds its modern equivalent in various genetic definitions of homology, only recently challenged by the emerging synthesis of evolutionary developmental biology. Finally, we conclude that Gegenbaur’s own careful methodological principles can serve as an important model for proponents of present day “evo-devo”, especially with respect to the integration of ontogeny with phylogeny embedded in comparative anatomy.  相似文献   

8.
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   

9.
10.
“Fire regime” has become, in recent decades, a key concept in many scientific domains. In spite of its wide spread use, the concept still lacks a clear and wide established definition. Many believe that it was first discussed in a famous report on national park management in the United States, and that it may be simply defined as a selection of a few measurable parameters that summarize the fire occurrence patterns in an area. This view has been uncritically perpetuated in the scientific community in the last decades. In this paper we attempt a historical reconstruction of the origin, the evolution and the current meaning of “fire regime” as a concept. Its roots go back to the 19th century in France and to the first half of the 20th century in French African colonies. The “fire regime” concept took time to evolve and pass from French into English usage and thus to the whole scientific community. This coincided with a paradigm shift in the early 1960s in the United States, where a favourable cultural, social and scientific climate led to the natural role of fires as a major disturbance in ecosystem dynamics becoming fully acknowledged. Today the concept of “fire regime” refers to a collection of several fire-related parameters that may be organized, assembled and used in different ways according to the needs of the users. A structure for the most relevant categories of parameters is proposed, aiming to contribute to a unified concept of “fire regime” that can reconcile the physical nature of fire with the socio-ecological context within which it occurs.  相似文献   

11.
We consider a previously unknown way of propagation of behavioural traditions in animal communities using hunting in ants as an example. We experimentally revealed that common litter dwelling ants Myrmica rubra effectively hunt jumping prey and the way the hunting behavioural pattern is distributed within ant colonies is rather sophisticated. Comparison of our results with those obtained on vertebrates enables us to suggest that “distributed social learning” plays an important role in spreading new traditions in animal communities: initial performances by a few carriers of an “at once and entirely” available behavioural pattern propagate this pattern among specimens which have only dormant “sketches” of it. Spread of these behaviours in populations is based on relatively simple forms of social learning such as social facilitation which underlies species’ predisposition to learn certain sequences of behavioural acts. To be triggered, carriers of dormant “sketches” of a relevant behavioural pattern should encounter performances of this pattern with sufficient frequency. We call this strategy triggering of dormant behavioural patterns. Integration of behaviour thus takes place not only at the individual level but at the population level as well.  相似文献   

12.
This paper describes, analyzes, and critiques the construction of separate “male” and “female” genomes in current human genome research. Comparative genomic work on human sex differences conceives of the sexes as like different species, with different genomes. I argue that this construct is empirically unsound, distortive to research, and ethically questionable. I propose a conceptual model of biological sex that clarifies the distinction between species and sexes as genetic classes. The dynamic interdependence of the sexes makes them “dyadic kinds” that are not like species, which are “individual kinds.” The concept of sex as a “dyadic kind” may be fruitful as a remedy to the tendency to conceive of the sexes as distinct, binary classes in biological research on sex more generally.  相似文献   

13.
Approximately 1 500 angiosperm species, in previous papers, have been sampled for the assessment of the amino acids (a. a.) in their nectar. We reaffirm that the findings provide statistically significant data linking differences in the concentration with pollinator type. Flowers that are pollinated by animals that have alternative sources of protein-building a. a.’s show lower a. a. concentration than those that are not. There is a tendency for woody plant nectar a. a.’s to be less concentrated than those of herbaceous plants, but there can be “phylogenetic constraints” which may reduce the correlations of a. a. concentration with pollinator type and with life form. The individual a. a.’s form complements which are qualitatively extremely constant within species. Proline is a normal constituent of many nectars and does not necessarily indicate contamination of the nectar by pollen. Criticism of our findings byGottsberger & al. (1984) is answered by reference to our previous publications and those of other workers, and to the presentation of data from California native species, not published previously. All previous postulates are borne out by these new data with the exception of positive correlations of a. a. concentration with “primitive” and “advanced” floral characteristics taken one at a time, which appear to be inconsistent and are affected strongly by the nature of the family in which they occur. Summary data are provided for families and genera which indicate that high or low a. a. concentration can typify certain families and genera of both relatively “primitive” and relatively “advanced” nature. Needs for future research on an ecosystem basis are quoted.  相似文献   

14.
Conclusion We must conclude that the sub-title of Bernal’s “The Social Function of Science” — “What science does: what science could do” is still the relevant challenge and indicates Bernal’s chief contribution, besides the foundation of molecular biology to our civilization. It is manifest that resources spent on armaments are a monstrous pathological symptom of our social structure. The ancient problem of “what is property” and what may be “owned” and by whom or by what organs of society is awakening.  相似文献   

15.
This article attempts to convey the joys and frustrations of skimming the Internet trying to find relevant information concerning an academic’s work as a scientist, a student or an instructor. A brief overview of the Internet and the “do’s and don’ts” for the neophyte as well for the more seasoned “navigator” are given. Some guidelines of “what works and what does not” and “what is out there” are provided for the scientist with specific emphasis for biologists, as well as for all others having an interest in science but with little interest in spending countless hours “surfing the net”. An extensive but not exhaustive list of related websites is provided.  相似文献   

16.
The bitunicate ascus paradigm recognized by E. S. Luttrell is reviewed. Species demonstrated to fit the paradigm are listed. Attempts to redefine the bitunicate ascus with functional as well as structural characters are outlined including Chadefaud’sTrois Catégories d’Ascomycetes, Sherwood’s Unusual Ascus Types, Bellemère’sCouche Plan, and Eriksson’s Ascus Dehiscence Types. Discussion of related topics include: (1) Characteristics of the bitunicate ascus including sequential wall formation, separation of wall regions at ascospore ejaculation, thenasse apicale, and the “banded pattern” of the secondary wall layer; (2) Ascus morphology types based on characters observable with the light microscope; and (3) Ascostromatic species designated bitunicate that deviate from the bitunicate ascus paradigm and yet are not structurally similar to the unitunicate ascomycetes. The separation of two wall regions at spore ejaculation is recognized as the single criterion for the bitunicate ascus sensu stricto (=fissitunicate). Le paradigme de l’asque bituniqué admis par E. S. Luttrell est revu et une liste des espèces qui manifestent ce paradigme est preséntée. Les essais de définer l’asque bituniqué par des caractères fonctionnels autant que des caractères structurais ont été tentés, viz., Chadefaud (“Trois Catégories d’Ascomycètes”), Sherwood (“Unusual Ascus Types”), Bellemère (“Couche Plan”), et Eriksson (“Ascus Dehiscence Types”). Des caractères de l’asque bituniqué sont presentés, comme la formation en ordre de la paroi, la séparation des régions de la paroi à l’éjaculation de l’ascospore, la nasse apicale, et aussi, la couche secondaire avec l’aspect bien strié. Les types morphologiques de l’asque que se fondent sur les caractères observables par le microscope de la lumière sont discutés. On présente une revue des espèces qui sont désignées “bituniqués”, mais qui devient du paradigme de l’asque bituniqué, en même temps qu’elles ne sont pas similaries aux ascomycetes unituniqués. La séparation de deux régiones de la paroi d’asque à l’éjaculation de l’ascospore est le seul critérium acceptée pour definer l’asque bituniqué sensu stricto (=fissitunquée).  相似文献   

17.
This essay argues that what makes “global health” “global” has more to do with configurations of space and time, and the claims to expertise and moral stances these configurations make possible, than with the geographical distribution of medical experts or the universal, if also uneven, distribution of threats to health. Drawing on a study of public–private partnerships supporting Botswana’s HIV/AIDS treatment program, this essay demonstrates ethnographically the processes by which “global health” and its quintessential spaces, namely “resource-limited” or “resource-poor settings,” are constituted, reinforced, and contested in the context of medical education and medical practice in Botswana’s largest hospital. Using Silverstein’s work on orders of indexicality, I argue that the terms of “global health” are best understood as chronotopic, and demonstrate how actors orient themselves and others spatio-temporally, morally, and professionally by using or refuting those terms. I conclude by arguing that taking “global health” on its own terms obscures the powerful forces by which it becomes intelligible. At stake are the frames within which medical anthropologists understand their objects of study, as well as the potential for the spaces of “global health” intervention to expand ever outward as American medical personnel attempt to calibrate their experiences to their expectations.  相似文献   

18.
Joseph Hooker first learned that Charles Darwin believed in the transmutation of species in 1844. For the next 14 years, Hooker remained a “nonconsenter” to Darwin’s views, resolving to keep the question of species origin “subservient to Botany instead of Botany to it, as must be the true relation”. Hooker placed particular emphasis on the need for any theory of species origin to support the broad taxonomic delimitation of species, a highly contentious issue. His always provisional support for special creation waned during the 1850s as he lost faith in its expediency for coordinating the study of plant geography, systematics and physiology. In 1858, Hooker embraced Darwin’s “considerable revolution in natural history,” but only after Darwin had carefully molded his transmutationism to meet Hooker’s exacting specifications.  相似文献   

19.
A four-site haplotype system at the dopamine D2 receptor locus (DRD2) has been studied in a global sample of 28 distinct populations. The haplotype system spans about 25 kb, encompassing the coding region of the gene. The four individual markers include three TaqI restriction site polymorphisms (RSPs) – TaqI “A”, “B”, and “D” sites – and one dinucleotide short tandem repeat polymorphism (STRP). All four of the marker systems are polymorphic in all regions of the world and in most individual populations. The haplotype system shows the highest average heterozygosity in Africa, a slightly lower average heterozygosity in Europe, and the lowest average heterozygosities in East Asia and the Americas. Across all populations, 20 of the 48 possible haplotypes reached a frequency of at least 5% in at least one population sample. However, no single population had more than six haplotypes reaching that frequency. In general, African populations had more haplotypes present in each population and more haplotypes occurring at a frequency of at least 5% in that population. Permutation tests for significance of overall disequilibrium (all sites considered simultaneously) were highly significant (P<0.001) in all 28 populations. Except for three African samples, the pairwise disequilibrium between the outermost RSP markers, TaqI “B” and “A”, was highly significant with D’ values greater than 0.8; in two of those exceptions the RSP marker was not polymorphic. Except for those same two African populations, the 16-repeat allele at the STRP also showed highly significant disequilibrium with the TaqI “B” site in all populations, with D’ values usually greater than 0.7. Only four haplotypes account for more than 70% of all chromosomes in virtually all non-African populations, and two of those haplotypes account for more than 70% of all chromosomes in most East Asian and Amerindian populations. A new measure of the amount of overall disequilibrium shows least disequilibrium in African populations, somewhat more in European populations, and the greatest amount in East Asian and Amerindian populations. This pattern seems best explained by random genetic drift with low levels of recombination, a low mutation rate at the STRP, and essentially no recurrent mutation at the RSP sites, all in conjunction with an “Out of Africa” model for recent human evolution. Received: 14 January 1998 / Accepted 19 March 1998  相似文献   

20.
The “Law of the Minimum” states that growth is controlled by the scarcest resource (limiting factor). This concept was originally applied to plant or crop growth (Justus von Liebig, 1840, Salisbury, Plant physiology, 4th edn., Wadsworth, Belmont, 1992) and quantitatively supported by many experiments. Some generalizations based on more complicated “dose-response” curves were proposed. Violations of this law in natural and experimental ecosystems were also reported. We study models of adaptation in ensembles of similar organisms under load of environmental factors and prove that violation of Liebig’s law follows from adaptation effects. If the fitness of an organism in a fixed environment satisfies the Law of the Minimum then adaptation equalizes the pressure of essential factors and, therefore, acts against the Liebig’s law. This is the the Law of the Minimum paradox: if for a randomly chosen pair “organism–environment” the Law of the Minimum typically holds, then in a well-adapted system, we have to expect violations of this law.  相似文献   

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