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1.
The concept of innateness is a part of folk wisdom but is also used by biologists and cognitive scientists. This concept has a legitimate role to play in science only if the colloquial usage relates to a coherent body of evidence. We examine many different candidates for the post of scientific successor of the folk concept of innateness. We argue that none of these candidates is entirely satisfactory. Some of the candidates are more interesting and useful than others, but the interesting candidates are not equivalent to each other and the empirical and evidential relations between them are far from clear. Researchers have treated the various scientific notions that capture some aspect of the folk concept of innateness as equivalent to each other or at least as tracking properties that are strongly correlated with each other. But whether these correlations exist is an empirical issue. This empirical issue has not been thoroughly investigated because in the attempt to create a bridge between the folk view and their theories, researchers have often assumed that the properties must somehow cluster. Rather than making further attempts to import the folk concept of innateness into the sciences, efforts should now be made to focus on the empirical questions raised by the debates and pave the way to a better way of studying the development of living organisms. Such empirical questions must be answered before it can be decided whether a good scientific successor – in the form of a concept that refers to a collection of biologically significant properties that tend to co-occur – can be identified or whether the concept of innateness deserves no place in science.  相似文献   

2.
Darwinian evolutionary biology has often been criticized for appealing to the notion of 'chance' in its explanations. According to some critics, such appeals exhibit the explanatory poverty of evolutionary theory. In response, defenders of Darwinism sometimes downplay the importance of 'chance' in evolution. I believe that both of these approaches are mistaken. The main thesis of this paper is that the term 'chance' encompasses a number of distinct concepts, and that at least some of these concepts serve essential explanatory functions in evolutionary biology. This claim is defended by way of an historical survey of the major concepts of 'chance' in the history of evolutionary biology, especially the concepts used by Jean Baptiste Lamarck, Charles Darwin, and Sewall Wright. An examination of their biologies shows how the concepts of 'chance' used cohere with their major scientific objectives and methods. These concepts survive and continue to function as important explanatory factors in contemporary evolutionary biology. Examples of such usage are given, and the explanatory status of 'chance' assessed.  相似文献   

3.
Although the connection of ecology with evolutionary idea and specifically with Darwinism was proclaimed for a long time it seems that Herbert Spencer's approach with its emphasize on natural equilibrium was much more often used as its real theoretical base. Elements of Darwinian approach appeared only in 1920-30s in works of those few researchers who studying the distribution and population dynamics of different species tried to understand general mechanisms providing their continuing existence. Later, in the middle of 1950s the first attempts were undertaken to consider the population life history (primarily the age specific schedule of death and reproduction) as a result of natural selection aimed to maintain the necessary level of fitness. A special attention in these studies that burgeoned in 1980-90s was paid to looking for various trade-offs between particular parameters of life history, e.g., between the survival of juveniles and fecundity of adults. The problem of life history optimization became central for the whole branch of science named "evolutionary ecology". Though traditionally this branch is connected with Darwinism, it is rooted rather in Spencer's ideas on moving equilibrium and deals more with static than dynamic. Disproportionately less attention was paid to the evolution of communities since these formations could be hardly interpreted as units of Darwinian selection. Moreover, the ecologists dealing with biosphere as a unified biogeochemical system began insist on "nondarwinian" nature of its evolution. The author considers this opinion as not sufficiently grounded. Darwin's ideas about unavoidable exponential growth, intrinsic for any population, consequent deficiency of resources, and differential survival and reproduction of individuals are still useful while studying the evolution of living organisms (phylogenetics) or the development of biosphere as a global ecosystem.  相似文献   

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The philosophical innateness debate has long relied onpsychological evidence. For a century, however, a parallel debate hastaken place within neuroscience. In this paper, I consider theimplications of this neuroscience debate for the philosophicalinnateness debate. By combining the tools of theoretical neurobiologyand learning theory, I introduce the ``problem of development' that alladaptive systems must solve, and suggest how responses to this problemcan demarcate a number of innateness proposals. From this perspective, Isuggest that the majority of natural systems are in fact innate. Lastly,I consider the acquistion strategies implemented by the human brain andsuggest that there is a rigorous way of characterizing these ``neuralconstructivist' strategies as not being strongly innate. Alternatives toinnateness are thus both rigorously definable and empirically supported.  相似文献   

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Neurohumoral stimulation comprising both autonomic-nervous-system dysfunction and activation of hormonal systems including the renin-angiotensin-aldosterone system (RAAS) was found to be associated with Type-2-diabetes (T2D). Therapeutic strategies such as RAAS interference proved to be beneficial in both T2D treatment and prevention. In addition to an activated RAAS, hyperleptinemia in obesity, hyperinsulinemia in conditions of peripheral insulin resistance and overall oxidative stress in T2D represent known activators of the sympathetic component of the autonomic nervous system. Here, we hypothesize that sympathetic activation may cause peripheral insulin resistance defined as partial blocking of insulin effects on glucose uptake. Resulting hyperinsulinemia or hyperglycemia-related oxidative stress may further aggravate sympatho-excitation. This notion leads to a secondary hypothesis: sympathetic activation worsens from obesity towards insulin resistance, and further towards T2D. In this review, existing evidence relating to neurohumoral stimulation in T2D and consequences thereof, such as oxidative stress and inflammation, are discussed. The aim of this review is to provide a rationale for therapies, which are able to intercept neuroendocrine pathways in T2D and precursor states such as obesity.  相似文献   

9.
The challenge hypothesis posits that when established social orders are challenged, plasma testosterone (T) in socially monogamous breeding male birds will temporarily increase to facilitate aggressive responses. However, not all birds conform to predictions. To expand upon past findings, we examined effects of direct territorial challenge on T levels in the blue tit (Cyanistes caeruleus). We found that simulated territorial intrusions caused a decline in plasma T during both territory establishment and laying/incubation. Conversely, corticosterone (CORT) levels dramatically increased. We also examined challenged blue tit males for levels of corticosterone-binding globulin (CBG), a carrier molecule that displays affinity for both CORT and T in birds. Although the CBG showed increased occupation by CORT during challenge, effects were not accompanied by a significant increase in the unbound T fraction. Thus, competitive hormone interactions on the CBG do not seem sufficient to explain changes in circulating T levels. To place our results within the context of past findings, we compared all socially monogamous birds tested to date for plasma levels of T during situational territorial intrusion experiments. We found that birds raising only one brood per season (e.g., the blue tit) consistently show no increase in plasma T but instead show elevations in circulating CORT. Thus, we suggest that single-broodedness plays an important role in determining patterns of hormone change and should be considered in future discussions of hormone-behavior interactions.  相似文献   

10.
While most researchers who use evolutionary theory to investigatehuman nature especially human sexuality describe themselves as ``interactionists', there is no clear consensus on the meaning of thisterm in this context. By interactionism most people in the fieldmean something like, both nature and nurture ``count' in thedevelopment of human psychology and behavior. Nevertheless, themultidisciplinary nature of evolutionary psychology results in a widevariety of interpretations of this general claim. Today, mostdebates within evolutionary psychology about the innateness of agiven behavioral characteristic or over its development turn as muchon which conception of ``innateness' and ``interactionism' theresearcher holds as on any empirical data they might derive.  相似文献   

11.
Subperiosteal approach as an improved concept for correction of the aging face   总被引:17,自引:0,他引:17  
A harmonious facial appearance is determined by a balanced relationship among all tissues of the face. With advancing age, balance is lost among the bone, muscle, fat, and skin as progressive changes occur in their volume, shape, position, and consistency. Study of clinical cases and fresh cadaver dissections has led to better understanding of the superficial musculoaponeurotic system (SMAS) and its relationship with the facial muscles and their bony insertions. From these anatomic studies we have developed an improved concept of rhytidectomy with the subperiosteal detachment of all soft tissues from the orbit, upper maxilla, malar bone, and nose. Following this detachment, the soft tissues of the cheek, forehead, jowls, nasolabial folds, lateral canthus, and eyebrows can be lifted to reestablish their youthful relationship with the underlying skeleton. Our 4-year experience includes 105 patients. Sixty percent of these patients were admitted to the hospital and had their procedure under general anesthesia; forty percent, however, had their procedure in an outpatient setting requiring only local anesthesia (lidocaine hydrochloride 1% plus epinephrine) and intravenous sedation (midazolam, ketamine). Complications have been minimal except for temporary paralysis of the frontal nerve in seven patients; guidelines for prevention have subsequently been developed. The subperiosteal rhytidectomy is excellent and appears more natural for rejuvenation of the upper and central face, eyebrows, periorbita, external canthus, cheeks, and nasolabial fold.  相似文献   

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The term "chance" has been given varied and different meanings in the history of occidental thought, carrying metaphysical connotations and controversial power. Despite the obscurity implied by this polysemy, this term is still frequently used without undergoing the conceptual clarifications that could locate its precise meaning and its original function in a theory. Here I propose a brief genealogical draft of this term and of its conceptual forms, from Aristotle to Darwin, to demonstrate the necessity of specifying what function it is fulfilling in each precise theoretical framework, in order not to be overwhelmed by the wide spectrum of the word.  相似文献   

14.
The health aspects and benefits of conception control as a justification for U.S. government support of family planning are reviewed. The Family Planning Services Act of 1970 set a goal of serving 5 million indigent women by 1975. It is predicted that the program will far surpass that goal. 340 million dollars were asked for contraceptive research by the federal government in fiscal year 1973, which is an example of the commitment to family planning by the government. Theoretical and sociopolitical reasons for family planning do not justify expenditure of public tax spending on population control assistance, but public health does justify those expenditures. Health and population control issues include the mental, physical, and social health of the parent and child, and broad demographic effects of age group population differentials, food supply, pollution, and health care services. The personal effects of an unwanted child are the most serious consequences of a lack of population control including economic and psychological hardship and damage. Maternal and infant mortality is related to age, economic status, and parity; e.g., toxemic pregnancy is more frequently found in young nulliparas. A correlation has been found between rapid parity and prematurity, though the research is not yet completely conclusive. Family planning through contraception and abortion can prevent unwanted pregnancies and unnecessary health risks from pregnancy by enabling parents to space and limit their families with safety. This is a highly desirable public health service goal and is emerging as a major concern of the federal government.  相似文献   

15.
This article makes the case for considering “unevenness” as a central theoretical concept for anthropology. By closely examining three case studies, from Latin American and the US, we develop a fourfold approach to the study of unevenness: the histories of particular connections and disconnections; spatial/scalar differentiation; state formation; and the development of labor. This approach is located at the intersection of history, geography, and anthropology and, we contend, is particularly useful for exploring the political struggles that lie at the heart of capitalist development and that unfold over time and across space in divergent, irregular ways.  相似文献   

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Liposuction abdominoplasty: an evolving concept   总被引:5,自引:0,他引:5  
Brauman D 《Plastic and reconstructive surgery》2003,112(1):288-98; discussion 299-301
Liposuction abdominoplasty-liposuction of abdominal subcutaneous tissue deep and superficial to Scarpa's fascia, with excision of excess abdominal skin and, when indicated, plication of the anterior rectus sheath without undermining-is an effective, low-risk approach to minimizing abdominal flap undermining. The technique allows aggressive thinning and "sculpting" of full-thickness abdominal subcutaneous tissue and achieves a natural (not featureless) abdominal contour. It minimizes the creation of "dead space," which often leads to postoperative complications, as well as preserves sensory nerve and blood supply to the abdominal skin. The operation may be performed with the patient under local anesthesia, which probably diminishes the risk for deep vein thrombosis. Moreover, additional procedures can be conducted safely and the postoperative course is short, uneventful, and without restrictions; patients return to normal activity within a week or so. New evaluation criteria for abdominoplasty are discussed in this article, the most important of which is the assessment of intraabdominal fat content and its impact on surgical outcome and the decision to perform anterior rectus sheath plication. The concept of a sliding, mobile, sensate abdominal flap, created by liposuction and sustained by multiple neurovascular mesenteries, is also offered.  相似文献   

18.
The cellulosome is an extracellular supramolecular machine that can efficiently degrade crystalline cellulosic substrates and associated plant cell wall polysaccharides. The cellulosome arrangement can also promote adhesion to the insoluble substrate, thus providing individual microbial cells with a direct competitive advantage in the utilization of the soluble hydrolysis products.  相似文献   

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Available evidence provides little support for a recent proposal that the term "trophoblast" be applied solely to eutherian mammals. Arguments for such a restricted usage are based on a dichotomous interpretation of therian reproduction that underestimates the developmental, structural, and functional diversity of trophoblastic tissues occurring within the infraclass Eutherian. The occurrence of developmental patterns that are phenotypically intermediate between those of commonly studied eutherians and metatherians suggests that blastocyst development is not fundamentally different in marsupials and eutherians. The trophoblast of marsupials accomplishes most or all of the major functions of the eutherian trophoblast, including maternal-fetal physiological exchange, implantation, contribution to placental membranes, steroid metabolism, and possibly, immunological protection of the conceptus. Furthermore, application of the term "trophoblast" to marsupials is consistent with present and past usage, as well as with the original definition and etymological derivation of the term. Therefore, we recommend that the term "trophoblast" continue to be applied in a functional-morphological sense to the appropriate extraembryonic tissues of marsupials. Such use of functional (rather than taxonomic) criteria for application of this term avoids biasing interpretations of mammalian reproductive evolution.  相似文献   

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