The founding father of sociobiology, Edward O. Wilson has recently turned his theory around by in... more The founding father of sociobiology, Edward O. Wilson has recently turned his theory around by inverting its basic hypothesis : the origins of sociality are no longer genetic but environmental. Many generations of sociobiologists are furious yet helpless against the media and scientific power of E. O. Wilson. This article is the story of a paradox, a treason and a change in paradigm.
Ce n'est desormais plus un secret, les inegalites economiques sont de retour, et elles atteig... more Ce n'est desormais plus un secret, les inegalites economiques sont de retour, et elles atteignent des sommets. Ce que l'on sait moins, c'est qu'elles sont tres toxiques pour les societes… Le probleme des…
As powerful tools for citizen participation that have drawn growing interest from the public and ... more As powerful tools for citizen participation that have drawn growing interest from the public and the media, transition initiatives have elicited concern from some within the Left due to their conspicuous silence on questions of inequality and social conflict. Is it an “apolitical” movement? What are the risks and the opportunities offered by these new practices and this new approach to politics?
Ce travail porte sur la dispersion des graines par les fourmis et se divise en deux parties : l’u... more Ce travail porte sur la dispersion des graines par les fourmis et se divise en deux parties : l’une experimentale (Chapitres 1, 2 & 3) et l’autre synthetique (Chapitres 4 & 5). L’approche experimentale a consiste en une exploration en conditions de laboratoire des comportements des fourmis a deux etapes du processus de myrmecochorie: a la source de graines et dans le nid. Des graines des plantes myrmecochores Viola odorata et Chelidonium majus ont ete presentees aux fourmis Lasius niger et Myrmica rubra. Chaque etape de la sequence myrmecochorique a genere une variabilite des comportements propre a chacun des quatre couples fourmis-graines. L’elaiosome n’attire pas les fourmis a distance. Les fourmis suivent toujours la meme sequence de comportements : antennation, manipulation et prise des graines. Le nombre d’antennations et de manipulations avant la prise de graines peut etre considere comme un indicateur de l’« hesitation » des fourmis a prendre les graines. L’espece a tendance ...
Although the Neotropical territorially dominant arboreal ant Azteca chartifex Forel is very aggre... more Although the Neotropical territorially dominant arboreal ant Azteca chartifex Forel is very aggressive towards any intruder, its populous colonies tolerate the close presence of the fierce polistine wasp Polybia rejecta (F.). In French Guiana, 83.33% of the 48 P. rejecta nests recorded were found side by side with those of A. chartifex. This nesting association results in mutual protection from predators (i.e., the wasps protected from army ants; the ants protected from birds). We conducted field studies, laboratory-based behavioral experiments and chemical analyses to elucidate the mechanisms allowing the persistence of this association. Due to differences in the cuticular profiles of the two species, we eliminated thepossibility of chemical mimicry. Also, analyses of the carton nests did not reveal traces of marking on the envelopes. Because ant forager flows were not perturbed by extracts from the wasps' Dufour's and venom glands, we rejected any hypothetical action of re...
In French Guiana, the arboreal nests of the swarm-founding social wasp Protopolybia emortualis (P... more In French Guiana, the arboreal nests of the swarm-founding social wasp Protopolybia emortualis (Polistinae) are generally found near those of the arboreal dolichoderine ant Dolichoderus bidens. These wasp nests are typically protected by an envelope, which in turn is covered by an additional carton 'shelter' with structure resembling the D. bidens nests. A few wasps constantly guard their nest to keep D. bidens workers from approaching. When alarmed by a strong disturbance, the ants invade the host tree foliage whereas the wasps retreat into their nest. Notably, there is no chemical convergence in the cuticular profiles of the wasps and ants sharing a tree. The aggressiveness of D. bidens likely protects the wasps from army ant raids, but the ants do not benefit from the presence of the wasps; therefore, this relationship corresponds to a kind of commensalism.
The founding father of sociobiology, Edward O. Wilson has recently turned his theory around by in... more The founding father of sociobiology, Edward O. Wilson has recently turned his theory around by inverting its basic hypothesis : the origins of sociality are no longer genetic but environmental. Many generations of sociobiologists are furious yet helpless against the media and scientific power of E. O. Wilson. This article is the story of a paradox, a treason and a change in paradigm.
Ce n'est desormais plus un secret, les inegalites economiques sont de retour, et elles atteig... more Ce n'est desormais plus un secret, les inegalites economiques sont de retour, et elles atteignent des sommets. Ce que l'on sait moins, c'est qu'elles sont tres toxiques pour les societes… Le probleme des…
As powerful tools for citizen participation that have drawn growing interest from the public and ... more As powerful tools for citizen participation that have drawn growing interest from the public and the media, transition initiatives have elicited concern from some within the Left due to their conspicuous silence on questions of inequality and social conflict. Is it an “apolitical” movement? What are the risks and the opportunities offered by these new practices and this new approach to politics?
Ce travail porte sur la dispersion des graines par les fourmis et se divise en deux parties : l’u... more Ce travail porte sur la dispersion des graines par les fourmis et se divise en deux parties : l’une experimentale (Chapitres 1, 2 & 3) et l’autre synthetique (Chapitres 4 & 5). L’approche experimentale a consiste en une exploration en conditions de laboratoire des comportements des fourmis a deux etapes du processus de myrmecochorie: a la source de graines et dans le nid. Des graines des plantes myrmecochores Viola odorata et Chelidonium majus ont ete presentees aux fourmis Lasius niger et Myrmica rubra. Chaque etape de la sequence myrmecochorique a genere une variabilite des comportements propre a chacun des quatre couples fourmis-graines. L’elaiosome n’attire pas les fourmis a distance. Les fourmis suivent toujours la meme sequence de comportements : antennation, manipulation et prise des graines. Le nombre d’antennations et de manipulations avant la prise de graines peut etre considere comme un indicateur de l’« hesitation » des fourmis a prendre les graines. L’espece a tendance ...
Although the Neotropical territorially dominant arboreal ant Azteca chartifex Forel is very aggre... more Although the Neotropical territorially dominant arboreal ant Azteca chartifex Forel is very aggressive towards any intruder, its populous colonies tolerate the close presence of the fierce polistine wasp Polybia rejecta (F.). In French Guiana, 83.33% of the 48 P. rejecta nests recorded were found side by side with those of A. chartifex. This nesting association results in mutual protection from predators (i.e., the wasps protected from army ants; the ants protected from birds). We conducted field studies, laboratory-based behavioral experiments and chemical analyses to elucidate the mechanisms allowing the persistence of this association. Due to differences in the cuticular profiles of the two species, we eliminated thepossibility of chemical mimicry. Also, analyses of the carton nests did not reveal traces of marking on the envelopes. Because ant forager flows were not perturbed by extracts from the wasps' Dufour's and venom glands, we rejected any hypothetical action of re...
In French Guiana, the arboreal nests of the swarm-founding social wasp Protopolybia emortualis (P... more In French Guiana, the arboreal nests of the swarm-founding social wasp Protopolybia emortualis (Polistinae) are generally found near those of the arboreal dolichoderine ant Dolichoderus bidens. These wasp nests are typically protected by an envelope, which in turn is covered by an additional carton 'shelter' with structure resembling the D. bidens nests. A few wasps constantly guard their nest to keep D. bidens workers from approaching. When alarmed by a strong disturbance, the ants invade the host tree foliage whereas the wasps retreat into their nest. Notably, there is no chemical convergence in the cuticular profiles of the wasps and ants sharing a tree. The aggressiveness of D. bidens likely protects the wasps from army ant raids, but the ants do not benefit from the presence of the wasps; therefore, this relationship corresponds to a kind of commensalism.
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