In this review,we show that predatory ants have a wide range of foraging behavior,something expected given their phylogenetic distance and the great variation in their colony size,life histories,and nesting habitats a...In this review,we show that predatory ants have a wide range of foraging behavior,something expected given their phylogenetic distance and the great variation in their colony size,life histories,and nesting habitats as well as prey diversity.Most ants are central-place foragers that detect prey using vision and olfaction.Ground-dwelling species can forage solitarily,the ancestral form,but generally recruit nestmates to retrieve large prey or a group of prey.Typically,ants are omnivorous,but some species are strict predators preying on detritivorous invertebrates or arthropod eggs,while those specialized on termites or other ants often have scouts that localize their target and then trigger a raid.They can use compounds that ease this task,including chemical insignificance,mimicry,and venoms triggering submissive behavior.Army ants include 8 Dorylinae and some species from other subfamilies,all having wingless queens and forming raids.Dorylinae from the Old World migrate irregularly to new nesting sites.The foraging of most New World species that prey on the brood of other ants is regulated by their biological cycle that alternates between a“nomadic phase”when the colony relocates between different places and a“stationary phase”when the colony stays in a bivouac constituting a central place.Among arboreal ants,dominant species forage in groups,detecting prey visually,but can use vibrations,particularly when associated with myrmecophytes.Some species of the genera Allomerus and Azteca use fungi to build a gallery-shaped trap with small holes under which they hide to ambush prey.展开更多
Aims One critical challenge for plants is to maintain an adequate nutrient supply under fluctuating environmental conditions.This is particularly true for epiphytic species that have limited or no access to the pedosp...Aims One critical challenge for plants is to maintain an adequate nutrient supply under fluctuating environmental conditions.This is particularly true for epiphytic species that have limited or no access to the pedosphere and often live in harsh climates.Bromeliads have evolved key innovations such as epiphytism,water-absorbing leaf trichomes,tank habit and Crassulacean acid metabolism(CAM)photosynthesis that enable them to survive under various environmental conditions.Bromeliads encompass diverse ecological types that live on different substrates(they can be terrestrial,epilithic or epiphytic)and vary in their ability to retain water(they can be tank-forming or tankless)and photosynthetic pathway(i.e.C3 or CAM).In this review,we outline the nutritional modes and specializations that enable bromeliads to thrive in a wide range of nutrient-poor(mostly nitrogen-depleted)environments.Important FindingsBromeliads have evolved a great diversity of morphologies and functional adaptations leading to the existence of numerous nutritional modes.Focusing on species that have absorptive foliar trichomes,we review evidence that bromeliads have evolved multi-faceted nutritional strategies to respond to fluctuations in the supply of natural nitrogen(N).These plants have developed mutualistic associations with many different and functionally diverse terrestrial and aquatic microorganisms and metazoans that contribute substantially to their mineral nutrition and,thus,their fitness and survival.Bacterial and fungal microbiota-assisted N provisioning,protocarnivory,digestive mutualisms and myrmecotrophic pathways are the main strategies used by bromeliads to acquire nitrogen.The combination of different nutritional pathways in bromeliads represents an important adaptation enabling them to exploit nutrient-poor habitats.Nonetheless,as has been shown for several other vascular plants,multiple partners are involved in nutrient acquisition indicating that there have been convergent adaptations to nutrient scarcity.Finally,we point out some gaps in the current knowledge of bromeliad nutrition that offer fascinating research opportunities.展开更多
Supercolonies of the red fire ant Solenopsis saevissima （Smith） develop in disturbed environments and likely alter the ant community in the native range of the species. For example, in French Guiana only 8 ant speci...Supercolonies of the red fire ant Solenopsis saevissima （Smith） develop in disturbed environments and likely alter the ant community in the native range of the species. For example, in French Guiana only 8 ant species were repeatedly noted as nesting in close vicinity to its mounds. Here, we verified if a shared set of biological, ecological, and behavioral traits might explain how these 8 species are able to nest in the presence of S. saevissima. We did not find this to be the case. We did find, however, that all of them are able to live in disturbed habitats. It is likely that over the course of evolution each of these species acquired the capacity to live syntopically with S. saevissima through its own set of traits, where colony size （4 species develop large colonies）, cuticular compounds which do not trigger aggressiveness （6 species） and submissive behaviors （4 species） complement each other.展开更多
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 reject...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,laboratorybased 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 the possibility 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 repulsive chemicals.Nevertheless,we noted that the wasps"scraped"the surface of the upper part of their nest envelope using their mandibles,likely removing the ants'scent trails,and an experiment showed that ant foragers were perturbed by the removal of their scent trails.This leads us to use the term"erasure hypothesis."Thus,this nesting association persists thanks to a relative tolerance by the ants towards wasp presence and the behavior of the wasps that allows them to"contain"their associated ants through the elimination of their scent trails,direct attacks,"wing-buzzing"behavior and ejecting the ants.展开更多
Ants, the most abundant taxa among canopy-dwelling animals in tropical rainforests, are mostly represented by territorially dominant arboreal ants （TDAs） whose territories are distributed in a mosaic pattern （arbor...Ants, the most abundant taxa among canopy-dwelling animals in tropical rainforests, are mostly represented by territorially dominant arboreal ants （TDAs） whose territories are distributed in a mosaic pattern （arboreal ant mosaics）. Large TDA colonies regulate insect herbivores, with implications for forestry and agronomy. What generates these mosaics in vegetal formations, which are dynamic, still needs to be better understood. So, from empirical research based on 3 Cameroonian tree species （Lophira alata, Ochnaceae; Anthocleista vogelii, Gentianaceae; and Barteriafistulosa, Passifloraceae）, we used the Self-Organizing Map （SOM, neural network） to illustrate the succession of TDAs as their host trees grow and age. The SOM separated the trees by species and by size for L. alata, which can reach 60 m in height and live several centuries. An ontogenic succession of TDAs from sapling to mature trees is shown, and some ecological traits are highlighted for certain TDAs. Also, because the SOM permits the analysis of data with many zeroes with no effect of outliers on the overall scatterplot distributions, we obtained ecological information on rare species. Finally, the SOM permitted us to show that functional groups cannot be selected at the genus level as congeneric species can have very different ecological niches, something particularly true for Crematogaster spp., which include a species specifically associated with B. fistulosa, nondominant species and TDAs. Therefore, the SOM permitted the complex relationships between TDAs and their growing host trees to be analyzed, while also providing new information on the ecological traits of the ant species involved.展开更多
基金provided by the French Agence Nationale de la Recherche,grant number:ANR-10-LABX-25-01.
文摘In this review,we show that predatory ants have a wide range of foraging behavior,something expected given their phylogenetic distance and the great variation in their colony size,life histories,and nesting habitats as well as prey diversity.Most ants are central-place foragers that detect prey using vision and olfaction.Ground-dwelling species can forage solitarily,the ancestral form,but generally recruit nestmates to retrieve large prey or a group of prey.Typically,ants are omnivorous,but some species are strict predators preying on detritivorous invertebrates or arthropod eggs,while those specialized on termites or other ants often have scouts that localize their target and then trigger a raid.They can use compounds that ease this task,including chemical insignificance,mimicry,and venoms triggering submissive behavior.Army ants include 8 Dorylinae and some species from other subfamilies,all having wingless queens and forming raids.Dorylinae from the Old World migrate irregularly to new nesting sites.The foraging of most New World species that prey on the brood of other ants is regulated by their biological cycle that alternates between a“nomadic phase”when the colony relocates between different places and a“stationary phase”when the colony stays in a bivouac constituting a central place.Among arboreal ants,dominant species forage in groups,detecting prey visually,but can use vibrations,particularly when associated with myrmecophytes.Some species of the genera Allomerus and Azteca use fungi to build a gallery-shaped trap with small holes under which they hide to ambush prey.
基金support from the Programme Convergence 2007-2013,Région Guyane from the European community(BREGA,ref.32080)an‘Investissement d’Avenir’grant managed by Agence Nationale de la Recherche(CEBA,ref.ANR-10-LABX-0025).
文摘Aims One critical challenge for plants is to maintain an adequate nutrient supply under fluctuating environmental conditions.This is particularly true for epiphytic species that have limited or no access to the pedosphere and often live in harsh climates.Bromeliads have evolved key innovations such as epiphytism,water-absorbing leaf trichomes,tank habit and Crassulacean acid metabolism(CAM)photosynthesis that enable them to survive under various environmental conditions.Bromeliads encompass diverse ecological types that live on different substrates(they can be terrestrial,epilithic or epiphytic)and vary in their ability to retain water(they can be tank-forming or tankless)and photosynthetic pathway(i.e.C3 or CAM).In this review,we outline the nutritional modes and specializations that enable bromeliads to thrive in a wide range of nutrient-poor(mostly nitrogen-depleted)environments.Important FindingsBromeliads have evolved a great diversity of morphologies and functional adaptations leading to the existence of numerous nutritional modes.Focusing on species that have absorptive foliar trichomes,we review evidence that bromeliads have evolved multi-faceted nutritional strategies to respond to fluctuations in the supply of natural nitrogen(N).These plants have developed mutualistic associations with many different and functionally diverse terrestrial and aquatic microorganisms and metazoans that contribute substantially to their mineral nutrition and,thus,their fitness and survival.Bacterial and fungal microbiota-assisted N provisioning,protocarnivory,digestive mutualisms and myrmecotrophic pathways are the main strategies used by bromeliads to acquire nitrogen.The combination of different nutritional pathways in bromeliads represents an important adaptation enabling them to exploit nutrient-poor habitats.Nonetheless,as has been shown for several other vascular plants,multiple partners are involved in nutrient acquisition indicating that there have been convergent adaptations to nutrient scarcity.Finally,we point out some gaps in the current knowledge of bromeliad nutrition that offer fascinating research opportunities.
文摘Supercolonies of the red fire ant Solenopsis saevissima （Smith） develop in disturbed environments and likely alter the ant community in the native range of the species. For example, in French Guiana only 8 ant species were repeatedly noted as nesting in close vicinity to its mounds. Here, we verified if a shared set of biological, ecological, and behavioral traits might explain how these 8 species are able to nest in the presence of S. saevissima. We did not find this to be the case. We did find, however, that all of them are able to live in disturbed habitats. It is likely that over the course of evolution each of these species acquired the capacity to live syntopically with S. saevissima through its own set of traits, where colony size （4 species develop large colonies）, cuticular compounds which do not trigger aggressiveness （6 species） and submissive behaviors （4 species） complement each other.
基金this study was provided by an“Investissement d’Avenir”grant managed by the French Agence Nationale de la Recherche(CEBA,ref.ANR-10-LABX-25-01).
文摘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,laboratorybased 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 the possibility 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 repulsive chemicals.Nevertheless,we noted that the wasps"scraped"the surface of the upper part of their nest envelope using their mandibles,likely removing the ants'scent trails,and an experiment showed that ant foragers were perturbed by the removal of their scent trails.This leads us to use the term"erasure hypothesis."Thus,this nesting association persists thanks to a relative tolerance by the ants towards wasp presence and the behavior of the wasps that allows them to"contain"their associated ants through the elimination of their scent trails,direct attacks,"wing-buzzing"behavior and ejecting the ants.
文摘Ants, the most abundant taxa among canopy-dwelling animals in tropical rainforests, are mostly represented by territorially dominant arboreal ants （TDAs） whose territories are distributed in a mosaic pattern （arboreal ant mosaics）. Large TDA colonies regulate insect herbivores, with implications for forestry and agronomy. What generates these mosaics in vegetal formations, which are dynamic, still needs to be better understood. So, from empirical research based on 3 Cameroonian tree species （Lophira alata, Ochnaceae; Anthocleista vogelii, Gentianaceae; and Barteriafistulosa, Passifloraceae）, we used the Self-Organizing Map （SOM, neural network） to illustrate the succession of TDAs as their host trees grow and age. The SOM separated the trees by species and by size for L. alata, which can reach 60 m in height and live several centuries. An ontogenic succession of TDAs from sapling to mature trees is shown, and some ecological traits are highlighted for certain TDAs. Also, because the SOM permits the analysis of data with many zeroes with no effect of outliers on the overall scatterplot distributions, we obtained ecological information on rare species. Finally, the SOM permitted us to show that functional groups cannot be selected at the genus level as congeneric species can have very different ecological niches, something particularly true for Crematogaster spp., which include a species specifically associated with B. fistulosa, nondominant species and TDAs. Therefore, the SOM permitted the complex relationships between TDAs and their growing host trees to be analyzed, while also providing new information on the ecological traits of the ant species involved.
