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21.
Cultural transmission and the evolution of cooperative behavior   总被引:5,自引:0,他引:5  
Sociobiological theory predicts that humans should not cooperate with large groups of unrelated individuals. This prediction is based on genetic models that show that selection acting on variation between large unrelated groups will generally be much weaker than selection acting on variation between individuals. Recently, several authors have presented related models of human evolution that integrate cultural and genetic transmission of behavior. We show that in such models group selection is potentially a strong force. Data on ethnocentrism is examined in the context of these results.  相似文献   
22.
A study of cultural transmission in Taiwan   总被引:1,自引:0,他引:1  
Our study of cultural transmission in Taiwan is based on a survey of 1000 students, their families, and friends, for characters ranging from religion to various customs and beliefs, as well as entertainment and hygienic habits. The effects of father, mother, and an older sib on a propositus are tested by an additive model of transmission, using a novel statistical procedure, and compared with correlations with friends. For many traits there exist significant influences; older sibs are almost as important as father and mother, with effects differing somewhat with their sex. Formulas for recurrences and equilibrium frequency of a cultural character for which father, mother, and sib are active in transmission are given in the appendices along with formulas for estimation of their effects from real data.This research was supported in part by grant NIH GM 20467 and NIH GM 20816. In early part of this investigation K.H.C. was supported by a grant to SIMS from the Alfred P. Sloan Foundation.  相似文献   
23.
Simultaneous inoculations of alfalfa with Meloidogyne hapla larvae and Ditylenchus dipsaci at 16, 20, 24, and 28 C did not depress penetration of either nematode in ''Nev Syn XX'' -a selection resistant to M. hapla and D. dipsaci, ''Vernal 298'' -a selection resistant to M. hapla and susceptible to D. dipsaci, ''Lahontan'' -a cultivar resistant to D. dipsaci and susceptible to M. hapla, and ''Ranger'' -a cultivar susceptible to both M. hapla and D, dipsaci. Infection with D. dipsaci depressed growth of susceptible ''Vernal 298'' and ''Ranger'' at all soil temperatures, except for ''Vernal 298'' at 16 C. Infection with M. hapla alone did not depress growth of any of the alfalfas. A combination of M. hapla and D. dipsaci resulted in a synergistic weight depression on ''Ranger'' at all soil temperatures. Inoculation of the four alfalfas with D. dipsaci 2, 4, 6, and 8 wk before inoculation with M. hapla at 16, 20, 24, and 28 C did not influence the resistance or susceptibility of ''Nev Syn XX,'' ''Lahontan,'' or ''Ranger.'' However, galling of ''Vernal 298'' by M. hapla was affected by soil temperature, plant age, and inoculation with D. dipsaci.  相似文献   
24.
Cultural evolutionists have long been interested in the problem of why fertility declines as populations develop. By outlining plausible mechanistic links between individual decision-making, information flow in populations and competition between groups, models of cultural evolution offer a novel and powerful approach for integrating multiple levels of explanation of fertility transitions. However, only a modest number of models have been published. Their assumptions often differ from those in other evolutionary approaches to social behaviour, but their empirical predictions are often similar. Here I offer the first overview of cultural evolutionary research on demographic transition, critically compare it with approaches taken by other evolutionary researchers, identify gaps and overlaps, and highlight parallel debates in demography. I suggest that researchers divide their labour between three distinct phases of fertility decline—the origin, spread and maintenance of low fertility—each of which may be driven by different causal processes, at different scales, requiring different theoretical and empirical tools. A comparative, multi-level and mechanistic framework is essential for elucidating both the evolved aspects of our psychology that govern reproductive decision-making, and the social, ecological and cultural contingencies that precipitate and sustain fertility decline.  相似文献   
25.
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26.
Wood-pastures are fragile ecosystems because they were formed by, and depend on specific, low-intensity multifunctional management. Although their ecological and cultural significance is high, wood-pastures are rapidly deteriorating all over Europe, mainly due to changing land use. We still lack a basic understanding of the ecological value of wood-pastures, and in which features they differ from other landscape elements. In this paper we investigated the ecological value of wood-pastures for passerine birds by (i) comparing bird assemblages of wood-pastures with those of closed forests and open pastures and (ii) exploring the relationships between variables describing wood-pastures and species traits of the bird assemblages. Our study region (Southern Transylvania, Romania) provides a unique opportunity to understand the importance of a traditional cultural and ecological environment for many different organisms. Wood-pastures had a higher overall number of bird species, and a higher spatial turnover in bird community composition than closed forests and open pastures. We found significant associations between bird species traits and habitat structural elements in wood-pastures such as large trees, oak- and pear trees and shrubs. Our findings suggest that traditional wood-pastures in Southern Transylvania have distinct and rich passerine bird communities. This richness is inextricably linked to the multifunctional, low-intensity land use traditionally applied in the wood-pastures that promotes high niche diversity. For effective conservation of the biodiversity of wood-pastures, a detailed understanding is needed of how different management regimes may influence the key structural elements of wood-pastures relevant for biodiversity and these should be protected.  相似文献   
27.
BOSCH, J., 1992. Floral biology and pollinators of three co-occurring Cistus species (Cistaceae). The pollination of three species of Cistus, Cistus albidus L., Cistus salvifolius L. and Cistus monspeliensis L. is studied. Insect visitors were censused and some were captured to analyse pollen distribution on their bodies. Floral phenology, breeding systems, some aspects of floral biology (pollen and nectar production, pollen-ovule ratios) and floral morphology were also studied for each species. Flowers of C. albidus produce more pollen and nectar than the other two species studied, and attract more insects, especially those with higher nutritional requirements. All three species are highly self-incompatible, but C. salvifolius and C. monspeliensis show some features that hinder xenogamy, and they have lower pollen-ovule ratios than C. albidus. As a result, this latter species apparently receives higher levels of cross-pollination, but at the cost of a higher investment to attract and reward reliable pollinators.  相似文献   
28.
王鑫   《生物信息学》2020,27(1):77-82
科学认识社会生态系统演进机制是对其进行有效管理的重要基础。以文化与政治生态学为理论基础,提出适合杭州—西湖社会生态系统的综合研究框架,识别了杭州—西湖社会生态系统的5个演进阶段,并分析出系统演进中的3种潜在状态。自然、政治、经济以及社会驱动力是影响杭州—西湖社会生态系统的主导因素,人类行为影响整个生态系统中扰动的频率、大小和形式并改变西湖生态系统的结构与功能,进而影响西湖为城市提供生态系统服务的潜能。在不同历史时期,基于自然、社会、经济、文化等多层面的需求,西湖在不同系统状态下为城市供给不同类别和质量的生态系统服务,总体而言供给与调节服务比例逐渐下降,文化服务逐渐上升,并且后者逐步成为最主要的生态系统服务类别。杭州与西湖在长期的互馈共生中建立了社会生态系统的自适应性调节机制,其背后的生态智慧可为现代风景园林规划提供重要启示。  相似文献   
29.
Onion maggot (Delia antiqua) is an economically important pest of Allium crops in temperate regions throughout the world. Management of this pest is necessary to achieve economic returns and depends on insecticide regimes and cultural management. Current cultural management especially altering planting date, field location and crop rotation depend on monitoring. We evaluated the effect of shape, size, colour and chemical attractants on trap catch of field populations of adult D. antiqua flies in upstate New York. White, large diameter, spherical traps in conjunction with Delia Lure attractant performed the best in attracting and catching D. antiqua adults. These results suggest an improved means of attracting and capturing D. antiqua populations which could be useful in monitoring efforts and development of attract and kill strategies for pest control.  相似文献   
30.
Biological pest control by means of beneficial organisms is for long part of agriculture and Integrated Pest Management (IPM). A new and efficient strategy to control the most common timber pest species in churches and museums, the furniture beetle Anobium punctatum (De Geer) (Coleoptera: Anobiidae), is based on the parasitoid wasp species Spathius exarator (Linnaeus) (Hymenoptera: Braconidae). Once this braconid wasp detects its host species beneath the surface, it pierces the wood with its ovipositor to lay one single egg onto the beetle larva. After hatching, the wasp larva feeds on the beetle larva thereby killing it. Afterwards, it pupates and emerges through a self-gnawed hole as an adult wasp. The tiny, 0.5-mm-wide exit hole can easily be distinguished from the 1- to 2-mm-wide exit hole of A. punctatum. Laboratory tests revealed that female wasps have an average life span of 85 days and produce a total of 24 offspring, when nutrition is provided. Between 2012 and 2019, braconid wasps were introduced into 54 different A. punctatum infested buildings. Treatment success was monitored by examining exit holes of new beetles and wasps thereby calculating corresponding parasitism rates. After the first year of treatment, parasitism rates were significantly higher with a mean value of 0.15 when compared to untreated objects with a natural parasitism and a mean value of 0.08 (n = 54). Following treatment of three objects over a period of eight years, parasitism rates continuously increased from 0.02 up to 0.31. In a church organ, which was treated during this period, the monitoring revealed a complete suppression of pest activity. These data prove that this biological method of pest control is an efficient, sustainable and non-toxic option to manage the common furniture beetle.  相似文献   
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