7,704 research outputs found
Dissonance reduction in nonhuman animals: Implications for cognitive dissonance theory
We review the evidence for dissonance reduction in nonhuman animals and examine the alternative explanations for these effects. If nonhuman animals engage in dissonance reduction, this supports the original theory as proposed by Festinger (1957) over the revisions to the theory that focused on the self-concept. Evidence of animal sentience, including dissonance reduction, may be a source of cognitive dissonance
Phase Zero
In October 2006 General Charles Wald, Deputy Commander U.S. European Com- mand, brought “Phase Zero” into the joint lexicon with the publication of an article, “The Phase Zero Campaign.”1 Over the last five years the concept of taking coordinated action in peacetime to affect the strategic environment has becomewidely accepted and is now integrated into theater campaign plans. These activi- ties focus on building capacity of partners and influencing potential adversaries to avoid war. In contrast, Chinese strategic culture has encouraged taking actions to defeat an enemy prior to the onset of hostilities for two and a half millennia
Mating system of the Eurasian badger, Meles meles, in a high density population
Badgers are facultatively social, forming large groups at high density. Group-living appears
to have high reproductive costs for females, and may lead to increased levels of inbreeding.
The extent of female competition for reproduction has been estimated from field data, but
knowledge of male reproductive success and the extent of extra-group paternity remains
limited. Combining field data with genetic data (16 microsatellite loci), we studied the mating
system of 10 badger social groups across 14 years in a high-density population. From 923
badgers, including 425 cubs, we were able to assign maternity to 307 cubs, with both parents
assigned to 199 cubs (47%) with 80% confidence, and 14% with 95% confidence. Age had a
significant effect on the probability of reproduction, seemingly as a result of a deficit of
individuals aged two years and greater than eight years attaining parentage. We estimate
that approximately 30% of the female population successfully reproduced in any given
year, with a similar proportion of the male population gaining paternity across the same
area. While it was known there was a cost to female reproduction in high density populations,
it appears that males suffer similar, but not greater, costs. Roughly half of assigned paternity
was attributed to extra-group males, the majority of which were from neighbouring social
groups. Few successful matings occurred between individuals born in the same social group
(22%). The high rate of extra-group mating, previously unquantified, may help reduce inbreeding,
potentially making philopatry a less costly strategy
Recent Loss of Vitamin C Biosynthesis Ability in Bats
The traditional assumption that bats cannot synthesize vitamin C (Vc) has been challenged recently. We have previously shown that two Old World bat species (Rousettus leschenaultii and Hipposideros armiger) have functional L-gulonolactone oxidase (GULO), an enzyme that catalyzes the last step of Vc biosynthesis de novo. Given the uncertainties surrounding when and how bats lost GULO function, exploration of gene evolutionary patterns is needed. We therefore sequenced GULO genes from 16 bat species in 5 families, aiming to establish their evolutionary histories. In five cases we identified pseudogenes for the first time, including two cases in the genus Pteropus (P. pumilus and P. conspicillatus) and three in family Hipposideridae (Coelops frithi, Hipposideros speoris, and H. bicolor). Evolutionary analysis shows that the Pteropus clade has the highest ω ratio and has been subjected to relaxed selection for less than 3 million years. Purifying selection acting on the pseudogenized GULO genes of roundleaf bats (family Hipposideridae) suggests they have lost the ability to synthesize Vc recently. Limited mutations in the reconstructed GULO sequence of the ancestor of all bats contrasts with the many mutations in the ancestral sequence of recently emerged Pteropus bats. We identified at least five mutational steps that were then related to clade origination times. Together, our results suggest that bats lost the ability to biosynthesize vitamin C recently by exhibiting stepwise mutation patterns during GULO evolution that can ultimately lead to pseudogenization
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