Search results for "territorialit"
showing 10 items of 57 documents
Territoriality versus flocking in the Zenaida dove (Zenaida aurita): resource polymorphism revisited using morphological and genetic analyses.
2011
11 pages; International audience; The term “resource polymorphism” refers to the existence of alternative phenotypes in relation to resource use, as a result of disruptive selection. Evidence for resource polymorphism is widespread in fish but remains scarce in birds. Although Zenaida Doves (Zenaida aurita) usually defend year-round territories, doves on Barbados can also be observed foraging at seed-storage sites in large flocks with little, if any, inter-individual aggression. On the basis of morphological variation, it has been suggested (Sol et al. 2005) that this represents a case of resource polymorphism, primarily driven by competition for territories. Using new data, we revisited th…
The Role of Spatial Exploration and Territoriality in Establishing Gilthead Seabream (Sparus aurata) Hierarchies, and Their Effects upon Underlying S…
2023
Territoriality, spatial exploration and social hierarchy are strictly related behaviors in gregarious fishes, and are often under-appreciated in farms where the individuals are confined within crowded spaces. In this study, we investigated the role of spatial exploration, elucidating the importance of time upon forming the social organization, and the role of the territoriality in gilthead seabream (Sparus aurata), using two experimental approaches. In the first approach, three fish were placed sequentially in the aquarium with an interval of two days (sequential model), while in the second (simultaneous model), two fish were simultaneously placed in an aquarium divided by a barrier which w…
Mesolithic pit-sites in Champagne (France): First data, key issues
2015
International audience; In less than a decade, more than 30 sites and around 200 deep pits dated to the Mesolithic have been identied in the Champagne-Ardenne region (north-eastern France). This paper describes the main characteristics of these features and provides some clues for their interpretation. This unexpected but apparently common type of site clearly implies a more marked territoriality and a greater social complexity than generally proposed for the period in continental northern France.
Poison frog social behaviour under global change: potential impacts and future challenges
2022
AbstractThe current and cascading effects of global change challenges the interactions both between animal individuals (i.e. social and sexual behaviour) and the environment they inhabit. Amphibians are an ecologically diverse class with a wide range of social and sexual behaviours, making them a compelling model to understand the potential adaptations of animals faced with the effects of human-induced rapid environmental changes (HIREC). Poison frogs (Dendrobatoidea) are a particularly interesting system, as they display diverse social behaviours that are shaped by conspecific and environmental interactions, thus offering a tractable system to investigate how closely related species may re…
Dalla “Sé-cattedrale” al “Sé-Nazione”. Sull’architettura della città e del territorio lusitano: chiavi di lettura storico-antropologiche
2010
La città è traccia architettonico-morfologica della storia che la produce. In pochi paesi l’urbe ha tracciata in sé, così chiaramente, l’evoluzione di questa storia, come in Portogallo, fra i più antichi per unità nazionale. L’articolo propone un percorso attraverso la formazione identitaria portoghese, dalla crescita economica, fasi coloniali, sino alla decadenza dell’economia marittima. Economia, questa, che anche attraverso l’urbe, come luogo privilegiato di sviluppo, decreta il vero inizio della globalizzazione planetaria. L’excursus storico si conclude con la crisi identitaria di fine Ottocento, per tracciare quello che è il profilo dell’immaginario nazionale portoghese, soprattutto co…
Tutela dell'ambiente e territorialità dell'azione ambientale
2009
La monografia di Gabriella Cangelosi è una trattazione ampia e intelligente di un tema attuale, in ordine al quale l'Autrice offre un chiarimento sistematico dei problemi inerenti alle tormentose e tormentate disposizioni che disciplinano una materia, il diritto ambientale, che si compone di una considerevole varietà di elementi. Il testo è saldamente impostato su quattro capitoli dedicati agli aspetti della tutela giuridica dell'ambiente, a diritto ed ambiente: dalle fonti della norma ambientale ai soggetti pubblici, ai profili generali del ruolo degli Enti locali, ai mezzi dell'azione amministrativa locale sull'ambiente. Nei confronti dei poteri pubblici e dei correlati assetti istituzion…
Basic knowledge of social hierarchies and physiological profile of reared sea bass Dicentrarchus labrax (L.).
2019
The effects of social hierarchies (dominant/subordinate individuals), such as aggressiveness, feeding order, and territoriality, are some of the characteristics used for describing fish behaviour. Social hierarchy patterns are still poorly understood in European-reared sea bass (Dicentrarchus labrax). In this work, we examine the social interactions among captive fish integrating behavioural and physiological profiles. Groups of three fish with EMG (electromyogram) radio transmitters were monitored for two weeks via video recording. Plasma levels of cortisol, glucose, lactate and lysozyme as well as haematological parameters such as haemoglobin, haematocrit and RBCC (red blood cell count) w…
The effect of male-male competition and ornament size on mean and variance of courtship intensity towards heterospecific and conspecific females
2015
Discrimination between hetero- and conspecifics is the elementary choice an individual performs when searching for potential mates. The level of selectivity and strength of species discrimination is modified by variance in the quality of females, level of the male’s reproductive investment, mate search costs, and the competitive environment. The effect of the competitive environment on both species discrimination and conspecific mate choice has seldom been studied simultaneously. We experimentally manipulated territorial competition ofCalopteryx splendensdamselfly males in the wild, and asked two questions. First, does increased competition influence the territorial males’ responses towards…
Vigilance and food intake rate in paired and solitary Zenaida DovesZenaida aurita
2011
We quantified vigilance during feeding in the Zenaida Dove Zenaida aurita, a tropical species with stable pair-bonds and year-round territoriality. Both males and females decreased the proportion of time spent vigilant by 30% when feeding with their partner compared with when feeding alone. This reduction was achieved through increasing the length of inter-scan duration, while scan duration remained constant. No evidence was found for coordination of vigilance between pair members. The equal investment in vigilance by male and female Zenaida Doves might be related to the mutual benefits of long-term pair-bonding.
Descent among the Wayú. Concepts and social meanings
2008
Descent among the Wayú. Concepts and social meanings. Taking the contemporary rethinking of the descent notion in Lowland South American ethnography as a starting point, the article provides an analysis of matrilineal descent among the Wayú. Using new ethnographical data, special attention is paid to indigenous concepts and to the way matrilineal descent articulates with other principles of social classification. By virtue of the role that matrilineal descent plays in defining territoriality and in feuds, the Wayú offer a very interesting case for rethinking the theoretical and comparative debate about the indigenous societies of Lowland South America and for reflecting on the complexity of…