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11.
Food sharing: a model of manipulation by harassment 总被引:3,自引:1,他引:2
Most analyses of food-sharing behavior invoke complex explanationssuch as indirect and delayed benefits for sharing via kin selectionand reciprocal altruism. However, food sharing can be a moregeneral phenomenon accounted for by more parsimonious, mutualisticexplanations. We propose a game theoretical model of a generalsharing situation in which food owners share because it is
in their own self-interestthey avoid high costs associatedwith beggar harassment. When beggars harass, owners may benefitfrom sharing part of the food if their consumption rate islow relative to the rate of cost accrual. Our model predictsthat harassment can be a profitable strategy for beggars if
they reap some direct benefits from harassing other than sharedfood (such as picking up scraps). Therefore, beggars may manipulatethe owner's fitness payoffs in such a way as to make sharingmutualistic. 相似文献
12.
Franz M. Wuketits 《Biology & philosophy》1986,1(2):191-206
Recently, biologist and philosophers have been much attracted by an evolutionary view of knowledge, so-called evolutionary epistemology. Developing this insight, the present paper argues that our cognitive abilities are the outcome of organic evolution, and that, conversely, evolution itself may be described as a cognition process. Furthermore, it is argued that the key to an adequate evolutionary epistemology lies in a system-theoretical approach to evolution which grows from, but goes beyond, Darwin's theory of natural selection. 相似文献
13.
《Bioscience, biotechnology, and biochemistry》2013,77(4):567-571
Casein was conjugated with dextran and galactomannan in a controlled dry state at a relative humidity of 79% and at 60°C for 24 hr. The covalent attachment of polysaccharides to casein was confirmed by SDS-PAGE and HPLC. The emulsifying activity of the casein-dextran and casein-galactomannan conjugates was 1.5 times higher than that of casein. The emulsion stability of the casein-dextran and casein-galactomannan conjugates was 10 times higher than that of casein. The improvement in these emulsifying properties reached a steady state when the conjugation of casein with polysaccharide was done for 24 hr in a controlled dry state, suggesting the rapid formation of conjugates through a Maillard reaction in the case of casein. Compared to commercial emulsifiers, the casein-polysaccharide conjugates showed better emulsifying properties in acidic and high-salt concentration systems. 相似文献
14.
《Current biology : CB》2022,32(1):74-85.e4
Download : Download video (38MB) 相似文献
15.
Kevin J. S. Zollman Carl T. Bergstrom Simon M. Huttegger 《Proceedings. Biological sciences / The Royal Society》2013,280(1750)
Costly signalling theory has become a common explanation for honest communication when interests conflict. In this paper, we provide an alternative explanation for partially honest communication that does not require significant signal costs. We show that this alternative is at least as plausible as traditional costly signalling, and we suggest a number of experiments that might be used to distinguish the two theories. 相似文献
16.
Effect Of Height On Tree Hydraulic Conductance Incompletely Compensated By Xylem Tapering 总被引:2,自引:0,他引:2
S. ZAEHLE 《Functional ecology》2005,19(2):359-364
17.
G. A. Doyle 《Human Evolution》1989,4(2-3):97-104
A mechanism is suggested, based on a biphasic approach-withdrawal theory proposed byT. C. Schneirla, to account for how behaviours may be selected by environmental forces for transmission over generations. The basic postulates
of Schneirla's theory are presented followed by an examination of some aspects of lorisid behaviour in the light of this theory. 相似文献
18.
Obiwu 《Dialectical Anthropology》2007,31(1-3):143-165
The African American Langston Hughes (1902–1967) and the Nigerian Nnamdi Azikiwe (1904–1996) were alumni of Lincoln University,
transatlantic culture warriors, and literary collaborators. In their friendship of thirty years, the two leaders of twentieth
century black discourse shared more in common than there had ever been in relationships between African and African American
elites. Surprisingly, very little attention has been paid to the meeting of two great minds who individually and collectively
stirred the imagination of their successors across Africa and the black Diaspora. By excavating the influences and unusual
similarities in their childhood and adult experiences and by a close reading of their poetry, this paper examines the cultural
kinship as well as the shared vision of social justice between Hughes and Zik.
Obiwu is a writer, literary historian, and comparative theorist. His publications include Rituals of the Sun (poetry collection), Igbos of Northern Nigeria (Diasporaic studies), and the seminal essay “The History of Nigerian literature, 1772–2006.” He is director of the writing
center at Central State University, Wilberforce, Ohio. 相似文献
19.
20.
The relationship between prominent visual imagery and emotion within dreams was investigated in relation to E. Hartmann's (1996) contextualizing image (CI) theory and M. Seligman and A. Yellen's (1987) dual imagery theory. Fifty-nine students recorded dreams over a 2-week period and submitted 115 dreams for analysis. Participants recorded ratings of emotion type and emotion intensity in each scene. Prominent visual images were identified and scored for intensity and detail by independent judges. As hypothesized from Hartmann's theory, there was a significant positive relationship between CI intensity and emotion intensity in the CI scene, emotion intensity generally peaked in the CI scene, and dreams containing a CI had higher overall ratings of emotion intensity than non-CI dreams. The result for the correlation of detail of prominent imagery with emotion was inconclusive, with a low positive correlation across CI scenes. This raises the possibility that the CI is not a unitary construct. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献