Phaeomelanin matters: Redness associates with inter-individual differences in behaviour and feather corticosterone in male scops owls (Otus scops)

Individuals within populations often show consistent variation in behavioural and physiological traits which are frequently inter-correlated, potentially leading to phenotypic integration. Understanding the mechanisms behind such integration is a key task in evolutionary ecology, and melanin based colouration has been suggested to play a pivotal role. In birds, most of plumage colour variation is determined by two types of melanin, eumelanin and phaeomelanin, but the role of phaeomelanin in avian phenotype integration has been barely investigated. Here, we test for covariation between phaeomelanin-based colouration, behavioural traits (i.e. nest territoriality, aggressiveness, breath rate and parental behaviour) and corticosterone in feathers in the polymorphic scops owl Otus scops, a bird species in which more phaeomelanic individuals display reddish colourations. In males, we observed that reddish males took longer to return to their nests and showed higher levels of feather CORT than more greyish ones. Behaviour and feather CORT were not associated to plumage colour in females. The found associations between redness, behaviour and feather CORT in males, but not in females, might suggest the existence of a sex-specific integrated phaeomelanic phenotype in scops owls.

Phaeomelanin matters: redness associates with inter-individual differences in behaviour and hormone profiles in male Scops owls (Otus scops)

Background: Individuals within populations often show consistent variation in behavioural and physiological traits, which are frequently inter-correlated, potentially leading to phenotypic integration. Understanding the mechanisms behind such integration is a key task in evolutionary ecology, and melanism has been suggested to play a pivotal role. In birds, most of plumage colour variation is determined by two types of melanin, eumelanin and phaeomelanin, but the role of melanin in avian phenotype integration has mostly been analysed in relation to eumelanin. Here we test for covariation between phaeo-melanin-based coloration, behavioural traits (i.e. nest territoriality, response against researchers, breath rate and parental behaviour) and corticosterone profiles in the polymorphic scops owl Otus scops , a bird species in which more phaeomelanic individuals display reddish colorations. Results: In males, we observed differences between red and grey individuals in latency to return to the nest after being disturbed and in feather CORT. Reddish males took longer to return to their nests and showed higher levels of feather CORT than grey ones. Behaviour and CORT profiles did not differ between red and grey females. Conclusions: The found associations between redness, behaviour and CORT in males, but not in females, might suggest the existence of a sex-specific integrated phaeomelanic phenotype, likely due to pleiotropy, in scops owls.

Division or Union of Labor? Analyzing Workers’ Representation in the Argentine Congress

Does social background affect legislators’ behavior in office? Do individuals with specific social ties tend to be mainly concerned with representing their group of reference, beyond partisanship? This article deals with these questions by analyzing bill-drafting patterns by representatives in the Argentine Congress who belong to an understudied group: workers. The wide presence of a broad, populist party (Peronism) that historically incorporated organized labor, along with other groups, provides consistent variation for empirical assessment. Evidence demonstrates that only labor-based representatives in general, regardless of party membership, tend to use legislative resources to target workers, while every other member of the populist party does not consider labor issues at all in their legislative tasks. Such findings open new directions for analysis of representation, legislative performance, and strategies developed by dissimilar groups in broad political organizations.

Prosodic Variation and Segmental Reduction and Their Roles in Cuing Turn Transition in Swedish

Prosody has often been identified alongside syntax as a cue to turn hold or turn transition in conversational interaction. However, evidence for which prosodic cues are most relevant, and how strong those cues are, has been somewhat scattered. The current study addresses prosodic cues to turn transition in Swedish. A perception study looking closely at turn changes and holds in cases where the syntax does not lead inevitably to a particular outcome shows that Swedish listeners are sensitive to duration variations, even in the very short space of the final unstressed syllable of a turn, and that they may use pitch cues to a lesser extent. An investigation of production data indicates that duration, and to some extent segmental reduction, demonstrate consistent variation in relation to the types of turn boundaries they accompany, while fundamental frequency and glottalization do not. Taken together, these data suggest that duration may be the primary cue to turn transition in Swedish conversation, rather than fundamental frequency, as some other studies have suggested.

In vitro concentration dependent detection of creatinine: a surface enhanced Raman scattering and fluorescence study

(a) SERS spectra and (b) fluorescence spectra of Jaffe complex showing consistent variation relatable to the concentration of CRN.