Search results for "Territoriality"
showing 10 items of 46 documents
State and nation in African constitutionalism : thematic study
2013
Only the State had a legal personality at the end of the 1789 Revolution. Derived from the phrase "[t] he State is the legal personification of a nation", the above-mentioned personality endows the first (state), to the detriment of the second (the nation), subjective rights. What about after the democratic revolution of 1989, that is to say, some two centuries later? This study attempts to show the revanche of the nation in legal theory from a context in which it was particularly bullied. On the one hand, the nation has a double mediate and immediate representation of the fact that it participates, with an initial legislative power, the formation of the general Will. We also know that the …
Interspecific territoriality in Calopteryx damselflies: the role of secondary sexual characters
2006
Interspecific territoriality is usually interpreted to result from interspecific interference competition, although it may also originate from mistaken species recognition. In the latter case, it may be based on similarity of secondary sexual characters. In the damselfly Calopteryx splendens, males have pigmented wing spots as a sexual character, and males with the largest spots resemble males of another species, Calopteryx virgo. Probably because of this resemblance, C. virgo males are more aggressive towards large- than small-spotted C. splendens males. We examined whether wing spot size of C. splendens males affects territorial interactions between the species. In a removal experiment, t…
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.
Species-specific song convergence in a moving hybrid zone between two passerines
2003
International audience; Moving hybrid zones are receiving increasing attention. However, so far little is known about the proximate mechanisms underlying these movements. Signalling behaviour, by individuals engaged in interspecific sexual and aggressive interactions, may play a crucial role. In this study, we investigated song variation within a moving hybrid zone between two warblers, Hippolais polyglotta and H. icterina . In these species, song is involved in interspecific territoriality and, probably, in mixed pairings. We showed that allopatric populations of the two species are clearly acoustically differentiated. However, interspecific differences faded out in sympatry as a result of…
Parasite-induced aggression and impaired contest ability in a fish host
2010
Abstract Background Success of trophically transmitted parasites depends to a great extent on their ability to manipulate their intermediate hosts in a way that makes them easier prey for target hosts. Parasite-induced behavioural changes are the most spectacular and diverse examples of manipulation. Most of the studies have been focused on individual behaviour of hosts including fish. We suggest that agonistic interactions and territoriality in fish hosts may affect their vulnerability to predators and thus the transmission efficiency of trophically transmitted parasites. The parasite Diplostomum spathaceum (Trematoda) and juvenile rainbow trout, Oncorhynchus mykiss, were used to study whe…
Habitat Differences and Variability in the Lek Mating System of Black Grouse
1996
Spatially fixed territoriality has been regarded to be a general feature in lek mating systems. In the absence of territories, however, the nature of leks may change remarkably. We compared leks of black grouse in areas, where territoriality was governed by habitat characteristics. On ice-covered lakes, where the lekking ground was homogeneous and offered no landmarks by which the displaying males would be able to recognize territory boundaries, the male aggregations were mobile. 'Classical' leks on bogs, however, were stable. It also appeared that on mobile leks, as compared to stable leks, the opportunities for females to choose their mates were reduced. The distribution of mating success…
Agonistic and sociable behaviors in the mound-building mice,Mus spicilegus: A comparative study withMus musculus domesticus
2001
Present social organization and mating systems result from selective pressures and ecological conditions but also from proximate interactions between individuals. Many studies report on a polygynous mating system with a social group territoriality in commensal populations of Mus musculus domesticus. However, little is known about the social organization of other Mus species living in outdoor conditions, such as the mound-building mouse Mus spicilegus. Comparative studies between M. m. domesticus and M. spicilegus have already shown behavioral differences in female sexual preferences and paternal care. To study agonistic and sociable interactions and gain insight into the social organization…
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.
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…
On the evolutionary stability of female infanticide
1997
Territoriality among female rodents may have evolved as an adaptation to intraspecific competition for resources or, alternatively, to defend pups against infanticide. In order to evaluate the latter, we analyse the conditions that allow an infanticidal strategy to invade a population of non-infanticidal females, and the circumstances under which infanticide may become an evolutionarily stable strategy (ESS). Our game theoretical analyses indicate that infanticide has to be associated with some direct (cannibalism) or indirect (reduced competition) resource benefits in order to invade a non-infanticidal population. We also expect that females will primarily kill litters of nearby neighbors,…