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1.
Ernst Mayr proposed a distinction between “proximate”, mechanistic, and “ultimate”, evolutionary, causes of biological phenomena. This dichotomy has influenced the thinking of many biologists, but it is increasingly perceived as impeding modern studies of evolutionary processes, including study of “niche construction” in which organisms alter their environments in ways supportive of their evolutionary success. Some still find value for this dichotomy in its separation of answers to “how?” versus “why?”questions about evolution. But “why is A?” questions about evolution necessarily take the form “how does A occur?”, so this separation is illusory. Moreover, the dichotomy distorts our view of evolutionary causality, in that, contra Mayr, the action of natural selection, driven by genotype-phenotype-environment interactions which constitute adaptations, is no less “proximate” than the biological mechanisms which are altered by naturally selected genetic variants. Mayr’s dichotomy thus needs replacement by more realistic, mechanistic views of evolution. From a mechanistic viewpoint, there is a continuum of adaptations from those evolving as responses to unchanging environmental pressures to those evolving as the capacity for niche construction, and intermediate stages of this can be identified. Some biologists postulate an association of “phenotypic plasticity” (phenotype-environment covariation with genotype held constant) with capacity for niche construction. Both “plasticity” and niche construction comprise wide ranges of adaptive mechanisms, often fully heritable and resulting from case-specific evolution. Association of “plasticity” with niche construction is most likely to arise in systems wherein capacity for complex learning and behavioral flexibility have already evolved.  相似文献   

2.
This is a biological approach to the philosophy of mind that feeds an investigation of the phenomena of “social” and “emotional”, both of which are widespread in nature. I scrutinize the non-dualistic Darwinian concept of the continuity of mind. For practical reasons, I address mind at different levels of organization: The systemic mind are the properties of which a common, coherent evolution works upon. Separated from this is “language-mind”: the crystallization of thought in words, which is a strictly human phenomenon. As the phenomenology of the body is a theory of philosophy that lie beyond language it can—to a certain extent—be extrapolated across a species boundary. In the process the phenomenology of the body comes to resemble biosemiotics and with this tool, I investigate a field study of social play behavior in canids. This leads to a possibility to study the non-human experience of emotion as “locally meaningful phenomena”.  相似文献   

3.
Every day, thousands of soil samples are collected from properties suspected of being contaminated. The samples are sent to laboratories where the chemical constituents are quantified. Frequently, one or more samples are identified as constituting a “hot spot” of soil contamination. The consequences of such a determination—more sampling, more remediation, more reporting—are often quite expensive. Yet despite the often costly consequences of identifying a “hot spot,” there appears no supportable methodology for objectively deciding which spots are “hot” and which are “not.” This can lead to situations where sampling episodes are required to demonstrate that there is not a problem, even though just exactly what would comprise a “problem” is not particularly clear and sometimes is not stated. The authors provide a review and analysis of common and published information concerning “hot spots.” They then present a different point of view about “hot spots” from those in common practice, a point of view that will challenge many environmental professionals to reconsider how they evaluate sampling results.  相似文献   

4.
Like many economic exchanges, industrial symbiosis (IS) is thought to be influenced by social relationships and shared norms among actors in a network. While many implicit references to social characteristics exist throughout the literature, there have been few explicit attempts to operationalize and measure the concepts. The “short mental distance,”“trust,”“openness,” and “communication” recorded among managers in Kalundborg, Denmark, set a precedent for examining and encouraging social interactions among key personnel in the dozens of eco‐industrial networks around the world. In this article we explore the relationships among various aspects of social embeddedness, social capital, and IS. We develop a conceptual framework and an approach using quantitative and qualitative methods to identify and measure these social characteristics, including social network structure, communication, and similarities in norms and conceptions of waste, and apply them in an industrial network in Nanjangud, South India. The findings suggest that there is a fairly high level of shared norms about dealing with waste—the “short mental distance”—in this network, but by‐product transactions are only weakly correlated with the structure and content of communication among managers. Replication of this approach can increase the understanding and comparability of the role of social characteristics in eco‐industrial activities around the world.  相似文献   

5.
The term “ethics” covers a multitude of virtues and possibly some sins where ethical perspectives differ. Given the diversity of ethical philosophies there is a question about what common ground can, or should, inform health research ethics. At a minimum it must be consistent with the law. Beyond that, ethics embraces a variety of possible approaches. This raises the question—what criteria are applied in determining the appropriate approach and what standards by way of quality control are applied to its decisional application by ethics committees or other authorities exercising responsibility in this difficult area. The particular issue of ethical perspectives on the use of “big data” in medical research also raises complex issues for consideration.  相似文献   

6.
Evidence is presented that, contrary to common scientific “belief”, larva digeneans have profound effects on various components at various levels of the littoral marine ecosystem. Their ecological capacity includes: —Reduction of the breeding potential of host populations by “parasitic castration”; —Structural modification of host populations by generation of erratic growth patterns, size-class differential mortality and “negative growth”; —Induction of host-population mortality and control by increased susceptibility to environmental stress; —Induction of changes in community structure by removal of hosts from their normal trophic levels; —Interference with major energy-flow pathways by precocious removal of hosts from their normal food-web position; —Interference with host-biomass, production and turnover-rate estimations by by-passing of hostassimilated energy; —Interference with predator-prey systems by affecting either component(s) of such systems.The notorious neglect of these factors by marine ecologists and, even more, their total unawareness of the effects these factors produce, raise serious doubts about the validity of marine ecological data and concepts. For the parasitologist, on the other hand, the study of ecological aspects of marine parasite (digenean) biology may open new avenues of research. With a true synthesis of both scientific disciplines, we may eventually arrive at a point where “more complete knowledge of life cycles will permit more intelligent and more effective regulatory methods, the reduction of morbidity, the advancement of health, and the conservation of natural resources.”The latter statement has not been cited from a recent issue of a scientific journal; it has been written down as long as 46 (!) years ago by one of the most outstanding investigators of marine digenean life cycles—Horace W. Stunkard (1940, p 15), but has lost nothing of its actuality. It is hoped that Stunkard's far-sighted words might encourage parasitologists to devote some of their scientific power and skill to the study of marine ecoparasitological problems—for the sake of a better understanding of ecological processes and to the benefit of the endangered marine life.  相似文献   

7.
Young children are thought to be particularly sensitive to heat waves, but relatively less research attention has been paid to this field to date. A systematic review was conducted to elucidate the relationship between heat waves and children’s health. Literature published up to August 2012 were identified using the following MeSH terms and keywords: “heatwave”, “heat wave”, “child health”, “morbidity”, “hospital admission”, “emergency department visit”, “family practice”, “primary health care”, “death” and “mortality”. Of the 628 publications identified, 12 met the selection criteria. The existing literature does not consistently suggest that mortality among children increases significantly during heat waves, even though infants were associated with more heat-related deaths. Exposure to heat waves in the perinatal period may pose a threat to children’s health. Pediatric diseases or conditions associated with heat waves include renal disease, respiratory disease, electrolyte imbalance and fever. Future research should focus on how to develop a consistent definition of a heat wave from a children’s health perspective, identifying the best measure of children’s exposure to heat waves, exploring sensitive outcome measures to quantify the impact of heat waves on children, evaluating the possible impacts of heat waves on children’s birth outcomes, and understanding the differences in vulnerability to heat waves among children of different ages and from different income countries. Projection of the children’s disease burden caused by heat waves under climate change scenarios, and development of effective heat wave mitigation and adaptation strategies that incorporate other child protective health measures, are also strongly recommended.  相似文献   

8.
PTC (phenylthiocarbamide) taste sensitivity was correlated with a measure of visual-motor maturation in children six to 15 years of age in two Ecuadorian Andean communities in which goiter (enlargement of the thyroid gland) and cretinism are endemic. The children in one population received injections of iodine in oil IM in 1966 while the children in the other population did not. The correlations between PTC taste sensitivity and visual-motor maturation were significant in both sex groups in the non-iodized population, but not in the iodized population. There was also a significant increase in taste sensitivity with age in the non-iodized, but not the iodized, population. The data support the hypothesis that the sensitive “tasters” of PTC limit their ingestion of naturally occurring goitrogens and are at an adaptive advantage with respect to the less sensitive “tasters” and “non-tasters” in this area in which iodine intake is low and the consumption of food crops containing naturally occurring goitrogens is high.  相似文献   

9.
It is increasingly common to quantify and describe behavioral variation in domestic and wild animals in terms of “personality”. Correlating behavioral traits are referred to as personality “dimensions” or “factors” and different dimensions have been reported in different species. “Boldness” is a well-described personality dimension in several species, although some issues remain unclear. Previous models of boldness include both novelty and risk taking, but recent studies indicate that these types of behaviors may reflect separate personality dimensions. In this study, we developed a behavioral test battery for domestic rabbits, and recorded behaviors of 61 individuals in four different situations (novel object, novel arena, social, and predator interactions). We used domestic rabbits as a model because behavioral variation in rabbits has rarely been quantified in terms of personality dimensions, although rabbit behavior is described. We also wanted to investigate behavioral variation in a Swedish rabbit breed of conservation concern — the Gotland rabbit. Factor analysis of the behavioral test measures suggested three personality dimensions: “exploration”, “boldness”, and “anxiety”. Novel object scores clustered in the exploration and boldness factors, whereas scores associated with predator interactions were explained by “anxiety”, indicating that novel object and anti-predator behavior reflect different personality dimensions in rabbits.  相似文献   

10.
Is there a special conservation biology?   总被引:1,自引:0,他引:1  
Reed Noss 《Ecography》1999,22(2):113-122
Conservation biology is special to the extent that it fills useful roles in the scientific and conservation fields that are not being filled by practitioners of other disciplines. The emergence of the “new conservation biology” in the late 1970's and its blossoming in the 1980's and 1990's reflect, to a large degree, a failure of traditional academic ecology and the natural resource disciplines to address modern conservation problems adequately. Yet, to be successful conservation biology, as an interdisciplinary field, must build on the strengths of other disciplines both basic and applied. The new conservation biology grew out of concern over extinction of species, although the field has expanded to include issues about management of several levels of biological organization. I examine four controversial questions of importance to conservation biologists today: 1) are there any robust principles of conservation biology? 2) Is advocacy an appropriate activity of conservation biologists? 3) Are we educating conservation biologists properly? 4) Is conservation biology distinct from other biological and resource management disciplines? I answer three of these questions with a tentative “yes” and one (3) with a regretful “in most cases, no.” I see a need for broader Training for students of conservation biology, more emphasis on collecting basic field data, compelling applications of conservation biology to real problems, increased influence on policy, and expansion of the international scope of the discipline. If all these occur, conservation biology will by truly special.  相似文献   

11.
The driving force behind the mixed-methods ethnoprimatological endeavor is to effectively conserve nonhuman primates. In this article, I argue that ethnoprimatological research can meet this goal only by discarding the purely science views of conservation that dominate the current literature. By considering more than local ecological perceptions, their ideological agendas, and their levels of power via a political ecology framework, ethnoprimatologists can simultaneously socialize the ecosystems we study and contribute our ethological skills to advance traditionally humanist disciplines’ increased attention to a wider field of agents and structures that matter. I support these arguments through an examination of farmer–green monkey (Chlorocebus sabaeus) relations in St. Kitts. Kittitian farmers’ narrative revealed three scales that collectively construct what is locally known as “the monkey problem:” increased rates of local contact between farmers and monkeys on farms, contestations over the future of St. Kitts’ land, and global debates over appropriate strategies to manage the monkey population. I show that although “the monkey problem” in St. Kitts does not involve an endangered or threatened species, my analysis of this construct has implications for primate populations that are threatened. This is because the root cause of this “problem”—the globalized discourse of nature conservation overpowering and problematizing local views about people–animal interactions—characterizes so many of the locales home to primates of conservation concern.  相似文献   

12.
How should we determine the distribution of psychological traits—such as Theory of Mind, episodic memory, and metacognition—throughout the Animal kingdom? Researchers have long worried about the distorting effects of anthropomorphic bias on this comparative project. A purported corrective against this bias was offered as a cornerstone of comparative psychology by C. Lloyd Morgan in his famous “Canon”. Also dangerous, however, is a distinct bias that loads the deck against animal mentality: our tendency to tie the competence criteria for cognitive capacities to an exaggerated sense of typical human performance. I dub this error “anthropofabulation”, since it combines anthropocentrism with confabulation about our own prowess. Anthropofabulation has long distorted the debate about animal minds, but it is a bias that has been little discussed and against which the Canon provides no protection. Luckily, there is a venerable corrective against anthropofabulation: a principle offered long ago by David Hume, which I call “Hume’s Dictum”. In this paper, I argue that Hume’s Dictum deserves a privileged place next to Morgan’s Canon in the methodology of comparative psychology, illustrating my point through a discussion of the debate over Theory of Mind in nonhuman animals.  相似文献   

13.
Common ancestry is a central feature of the theory of evolution, yet it is not clear what “common ancestry” actually means; nor is it clear how it is related to other terms such as “the Tree of Life” and “the last universal common ancestor”. I argue these terms describe three distinct hypotheses ordered in a logical way: that there is a Tree of Life is a claim about the pattern of evolutionary history, that there is a last universal common ancestor is an ontological claim about the existence of an entity of a specific kind, and that there is universal common ancestry is a claim about a causal pattern in the history of life. With these generalizations in mind, I argue that the existence of a Tree of Life entails a last universal common ancestor, which would entail universal common ancestry, but neither of the converse entailments hold. This allows us to make sense of the debates surrounding the Tree, as well as our lack of knowledge about the last universal common ancestor, while still maintaining the uncontroversial truth of universal common ancestry.  相似文献   

14.
“Air (aire, also aigre) in the body” is a frequent explanation of illness according to the traditional medical beliefs in Mexico. Anthropologists have generally scrutinized aire in the context of other common folk illnesses treated by traditional healers (curanderas). However, drawing on my research in the communities of Northern Oaxaca I suggest that aire occupies a more distinct position in the folk medical cosmology than it has usually been credited with. This distinction rests on the notion’s exceptional ambivalence and openness to multiple interpretations. “Air” is recurred to as the cause of illness mainly in situations where every other explanation, either “traditional” or “biomedical,” seems to be inadequate. The physical properties of air—its transparency, invisibility, apparent immateriality, near omnipresence, and virtual “nothingness”—render it a suitable explanation of the last resort. Local understandings of what aire “is” are often vague and elusive, and in many respects the term functions in folk medical discourse as an “empty signifier.”  相似文献   

15.
A central tenet of molecular biology is that heritable information is stored in nucleic acids. However, this paradigm has been overturned by a group of proteins called “prions.” Prion proteins, many of which are intrinsically disordered, can adopt multiple conformations, at least one of which has the capacity to self-template. This unusual folding landscape drives a form of extreme epigenetic inheritance that can be stable through both mitotic and meiotic cell divisions. Although the first prion discovered—mammalian PrP—is the causative agent of debilitating neuropathies, many additional prions have now been identified that are not obviously detrimental and can even be adaptive. Intrinsically disordered regions, which endow proteins with the bulk property of “phase-separation,” can also be drivers of prion formation. Indeed, many protein domains that promote phase separation have been described as prion-like. In this review, we describe how prions lie at the crossroads of phase separation, epigenetic inheritance, and evolutionary adaptation.  相似文献   

16.
It has long been assumed that serial homologues are ancestrally similar—polysomerism resulting from a “duplication” or “repetition” of forms—and then often diverge—anisomerism, for example, as they become adapted to perform different tasks as is the case with the forelimb and hind limbs of humans. However, such an assumption, with crucial implications for comparative, evolutionary, and developmental biology, and for evolutionary developmental biology, has in general not really been tested by a broad analysis of the available empirical data. Perhaps not surprisingly, more recent anatomical comparisons, as well as molecular knowledge of how, for example, serial appendicular structures are patterned along with different anteroposterior regions of the body axis of bilateral animals, and how “homologous” patterning domains do not necessarily mark “homologous” morphological domains, are putting in question this paradigm. In fact, apart from showing that many so-called “serial homologues” might not be similar at all, recent works have shown that in at least some cases some “serial” structures are indeed more similar to each other in derived taxa than in phylogenetically more ancestral ones, as pointed out by authors such as Owen. In this article, we are taking a step back to question whether such assumptions are actually correct at all, in the first place. In particular, we review other cases of so-called “serial homologues” such as insect wings, arthropod walking appendages, Dipteran thoracic bristles, and the vertebrae, ribs, teeth, myomeres, feathers, and hairs of chordate animals. We show that: (a) there are almost never cases of true ancestral similarity; (b) in evolution, such structures—for example, vertebra—and/or their subparts—for example, “transverse processes”—many times display trends toward less similarity while in many others display trends toward more similarity, that is, one cannot say that there is a clear, overall trend to anisomerism.  相似文献   

17.
As regards the history of its flora, the island of Rodriguez bears a striking resemblance to St. Helena. We read of the latter island that fire, goats, and finally introduced foreign plants well nigh exterminated the indigenous flora; and the same causes have operated and, I regret to say, are still operating in Rodriguez. The result is that the primitive vegetation has been in great part destroyed, leaving the island a field for the rank and rapid growth of common tropical weeds. The old and luxuriant vegetation of two hundred years ago—thus quaintly described by Leguat*, “We could hardly take our eyes off from the little mountains of which the island entirely consists; they are so richly spread with great and tall trees,” and, again, “‘Tis as I have hinted, composed of lovely hills covered all with fine trees whose perpetual verdure is entirely charming”—has now, to a large extent, disappeared, and is represented by only a few species, many of which are confined to the more unfrequented and less accessible places. It is indeed difficult to recognize in the barren and arid Rodriguez of the present day the “little Eden,”“lovely isle,”“earthly paradise” of Leguat. The flora, as it now exists, is an exceedingly fragmentary one; it is therefore a matter of some difficulty to determine its exact limits and to draw conclusions as to its affinities with the floras of other oceanic islands and of adjacent continents. This is the more to be regretted, as, from the geographical position of the island and the physical condition of climate to which it is subject, its flora might be expected, whether taken singly or as part of that of the Mascarene group, to contribute very important data towards the solution of the problem of the distribution of plant‐life in that region. The following general statements may, however, be made:—  相似文献   

18.
The author previously described special sensitivity measures for diversity indices. These measures make possible on analytical treatment of the index sensitivity. In the article a detailed analysis of sensitivity properties of the Hurlbert indices is presented. In the first step the abundances nk were sequenced in an increasing order. Plotting the sensitivity against nk or log nk, essential sensitivity properties can be observed. For example, one can study the sensitivities to changes in the dominant and subdominant abundances, the site of the “nearly neutral” abundance and the site of local sensitivity maxima in the domain of the relatively rare categories. The observations are supported by mathematical reasoning.  相似文献   

19.
《Ecological Indicators》2008,8(5):466-475
Measures used to describe the floristic structure of a habitat can vary in their ability to express trends in plant composition along anthropogenic disturbance gradients. This study was based on a survey of vascular plant biodiversity performed along stream bank habitats within an agricultural landscape in southeastern Ontario, Canada. The accuracy of several measures of plant biodiversity – including those related to a regional floristic quality assessment system – was examined to compare their ability to recognize a gradient of anthropogenic disturbance and associated floristic quality along the stream bank habitats. The floristic quality assessment system is a scheme in which all vascular plants of a region have been assigned a score corresponding to a qualitative conservation value based on habitat fidelity and tolerance of disturbance (native species), and on invasiveness (non-native species). Data were collected from a priori designated disturbed, moderate, and pristine zones along 27 stream sections exhibiting a length-wise disturbance gradient. A detrended correspondence analysis (DCA) was used to isolate the plant compositional gradient present along the stream sections. The measures of plant biodiversity recorded in the different study sites were then ranked by the degree to which they were linearly correlated with the identified compositional gradient of the DCA. The “% non-native plant species” measure was most effective at expressing the gradient, though it incorporated nothing about the fidelity and sensitivity of native plant species present in individual zones. Several measures associated with the floristic quality assessment system – including the mean coefficient of “conservatism” (mCC) – were also effective in identifying the gradient, and had the additional benefit of considering the contribution of each native species in a plot. The simple measure of “total plant species richness” proved to be a poor linear indicator due to a quadratic trend across the whole of the compositional gradient. The floristic quality assessment system proved to be a valuable tool for assessing conservation values of the selected sites. It should be extended to include further regions in Canada and North America in general. Our results further suggest that stream banks associated with open non-crop agricultural property are highly susceptible to colonization by non-native upland plants and species of low conservation interest, and that the presence of wooded areas surrounding these same streams is associated with higher numbers of native and disturbance sensitive plant species present in the bank habitats.  相似文献   

20.
Cognitive and evolutionarily-minded researchers have increasingly adopted the “Who Said What?” memory-confusion paradigm, a powerful and sensitive paradigm originating from social psychology which allows researchers to unobtrusively measure social categorization. The paradigm has been particularly important over the past two decades for arbitrating between different functionalist hypotheses about the evolved social mind. Bor (2018) has pointed out, however, that the simple arithmetic base-rate correction inherited from social psychology for this paradigm is problematic. This standard base-rate correction—in use since 1992 and in over a dozen studies—creates a mathematical artifact in which the calculated magnitude of categorization by one dimension can affect the calculated magnitude of categorization by a second, crossed dimension, even when the two dimensions are in fact fully independent from one another. No one had noticed this in 25?years. Worryingly, this means that all previously-reported “Who Said What?” studies featuring two crossed dimensions have reported potentially-biased estimates of the true magnitude of categorization. Here, a reanalysis of four large research projects is presented, involving 56 effect sizes across 31 between-subjects conditions (Pietraszewski, Cosmides, & Tooby, 2014; Pietraszewski & Schwartz, 2014; Pietraszewski, Curry, Petersen, Cosmides, & Tooby, 2015; Pietraszewski, 2016). In all cases, results from those papers hold or are even strengthened by the reanalysis. In particular, the previously-reported experimental reductions in racial categorization were in fact underestimates. This reanalysis also reveals that the most common artifact of the previously-used error correction was to artificially-inflate categorization by the weaker of the two dimensions—at least among the studies reported here. Finally, a succinct list of best practices for use of the “Who Said What?” paradigm in the future is presented, including but not limited to this new base-rate correction.  相似文献   

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