Male–male combats in a polymorphic lizard: residency and size,but not color,affect fighting rules and contest outcome

Theoretical models predict that the outcome of dyadic agonistic encounters between males is influenced by resource‐holding potential, resource value, and intrinsic aggressiveness of contestants. Moreover, in territorial disputes residents enjoy a further obvious competitive advantage from the residency itself, owing to the intimate familiarity with their territory. Costs of physical combats are, however, dramatically high in many instances. Thus, signals reliably reflecting fighting ability of the opponents could easily evolve in order to reduce these costs. For example, variation in color morph in polymorphic species has been associated with dominance in several case studies. In this study, we staged asymmetric resident‐intruder encounters in males of the common wall lizard Podarcis muralis, a species showing three discrete morphs (white, yellow, and red) to investigate the effects of asymmetries in color morph, residency, and size between contestants on the outcome of territorial contests. We collected aggression data by presenting each resident male with three intruders of different color morph, in three consecutive tests conducted in different days, and videotaping their interactions. The results showed that simple rules such as residency and body size differences could determine the outcome of agonistic interactions: residents were more aggressive than intruders, and larger males were competitively superior to smaller males. However, we did not find any effect of color on male aggression or fighting success, suggesting that color polymorphism in this species is not a signal of status or fighting ability in intermale conflicts. Aggr. Behav. 35:274–283, 2009. © 2009 Wiley‐Liss, Inc.     

Different involvement of type 1, 2, and 3 ryanodine receptors in memory processes

The administration of the ryanodine receptor (RyR) agonist 4-Cmc (0.003-9 nmol per mouse intracerebroventricularly [i.c.v.]) ameliorated memory functions, whereas the RyR antagonist ryanodine (0.0001-1 nmol per mouse i.c.v.) induced amnesia in the mouse passive avoidance test. The role of the type 1, 2, and 3 RyR isoforms in memory processes was then evaluated by inhibiting the expression of the three RyR proteins in the mouse brain. A selective knockdown of the RyR isoforms was obtained by the i.c.v. administration of antisense oligonucleotides (aODNs) complementary to the sequence of RyR1, RyR2 and RyR3 proteins, as demonstrated by immunoblotting experiments. RyR1 (5-9 nmol per mouse i.c.v.) knockdown mice did not show any memory dysfunction. Conversely, RyR2 (1-7 nmol per mouse i.c.v.) and RyR3 (1-7 nmol per mouse i.c.v.) knockdown animals showed an impairment of memory processes. This detrimental effect was temporary and reversible, disappearing 7 d after the end of the aODN treatment. At the highest effective doses, none of the compounds used impaired motor coordination, as revealed by the rota rod test, nor modified spontaneous mobility and inspection activity, as revealed by the hole-board test. In conclusion, the lack of any involvement of cerebral RyR1 was demonstrated. These findings also showed the involvement of type 2 and type 3 RyR in the modulation of memory functions identifying these cerebral RyR isoforms as critical targets underlying memory processes.     

Toleration as the Balance Between Liberty and Security

The Journal of Ethics - Traditionally, an adequate strategy to deal with the tension between liberty and security has been toleration, for the latter allows the maximization of individual liberty...     

Linguistic Justice and Analytic Philosophy

Abstract

This paper investigates whether analytic philosophers who are non-native English speakers are subject to linguistic injustice and, if yes, what kind of injustice that is and whether it is different from the general disadvantage that non-native English speakers meet in a world where English is rapidly becoming the lingua franca. The paper begins with a critical review of the debate on linguistic justice, with a particular focus on the emergence of a lingua franca and the related questions of justice, both in terms of the disadvantages suffered by those groups who bear the cost of learning another language and in terms of forms of discrimination due to accents and language improprieties. We argue that being at a relative disadvantage compared to others does not necessarily translate in a proper injustice if fundamental civil, political and social provisions are in place. We suggest that a circumstance of injustice arises when such disadvantage affects those who are not yet members of such academic community such as prospective students, thus contributing in keeping the non-native group a minority. We qualify this case of disadvantage as a matter of structural injustice.     

Do We Need Toleration as a Moral Virtue?

In this essay, I reconstruct tolerance as a moral virtue, by critically analysing its definition, circumstances, justification and limits. I argues that, despite its paradoxical appearance, tolerance qualifies as a virtue, by means of a restriction of its proper object to differences that are chosen. Since this excludes the most important and divisive differences of contemporary pluralism from the scope of the virtue of tolerance, the moral model of toleration cannot constitute the micro-foundation of the corresponding political practice. However, if the political ideal of toleration must be founded on independent political reasons of justice, the moral model can bridge the gap between private morality and public reason, providing citizens with moral motives to supplement the political obligation to neutrality. This revised version was published online in August 2006 with corrections to the Cover Date.