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241.
We report an experimental investigation into whether domesticated dogs display contagious yawning. Fifteen dogs were shown
video clips of (1) humans and (2) dogs displaying yawns and open-mouth expressions (not yawns) to investigate whether dogs
showed contagious yawning to either of these social stimuli. Only one dog performed significantly more yawns during or shortly
after viewing yawning videos than to the open-mouth videos, and most of these yawns occurred to the human videos. No dogs
showed significantly more yawning to the open-mouth videos (human or dog). The percentage of dogs showing contagious yawning
was less than chimpanzees and humans showing this behavior, and considerably less than a recently published report investigating
this behavior in dogs (Joly-Mascheroni et al. in Biol Lett 4:446–448, 2008). 相似文献
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Environmental and Behavioral Influences on Gene Activity 总被引:1,自引:0,他引:1
Gilbert Gottlieb 《Current directions in psychological science》2000,9(3):93-97
The central dogma of molecular biology holds that 'information' flows from the genes to the structure of the proteins that the genes bring about through the formula DNA → RNA → protein. In this view, a set of master genes activates the DNA necessary to produce the appropriate proteins that the organism needs during development. In contrast to this view, probabilistic epigenesis holds that necessarily there are signals from the internal and external environment that activate DNA to produce the appropriate proteins. To support this view, I review a substantial body of evidence showing that external environmental influences on gene activation are normally occurring events in a large variety of organisms, including humans. This demonstrates how genes and environments work together to produce functional organisms, thus extending the model of probabilistic epigenesis. 相似文献
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Christopher Gilbert 《Pacific Philosophical Quarterly》2005,86(2):201-224
Abstract: While Augustine distinguishes free choice from true liberty, his account of human freedom implies further distinctions which Augustine himself does not make explicit. More importantly, Augustine regards these distinct types of freedom as qualitatively different; some are clearly superior to others. Descartes also distinguishes qualitatively different types of freedom, and does so in a way that parallels Augustine's view. I here argue that Augustine divides freedom into four qualitatively distinct grades, and then demonstrate that Descartes’ account of freedom is a rationalist adaptation of the theory of free choice found in Augustine. 相似文献
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