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Soares P.A.O.,Federal University of Vicosa | Delabie J.H.C.,Upa Laboratorio Of Mirmecologia | Zanuncio J.C.,Federal University of Vicosa | Serratildo J.E.,Federal University of Vicosa
Sociobiology | Year: 2011

This study examined post-embryonic brain development in workers and males of the ant Camponotus rufipes (Fabricius, 1775) and its associations with ecdysteroid titers in haemolymph. Ecdysteroid levels were lower in the prepupae and the early pupae of workers, whereas they were higher in the prepupae and early pupae of males. In workers, brain volume increased 25% from the prepupal to the adult stages. In contrast, the brain volume of males decreased from the prepupal to weakly-pigmented eyed pupal stages, which followed a volume increase from the medium-pigmented eyed pupal to adult stages. These results suggest that ecdysteroids might be related to the brain development ofpupae, as the high titers in early pupae followed by its decrease at the end of pupal development coincided with brain crescent development in workers and males. Source

Dejean A.,CNRS Functional Ecology & Environment Laboratory | Groc S.,French National Center for Scientific Research | Herault B.,CIRAD UMR CIRAD 93 | Rodriguez-Perez H.,French National Center for Scientific Research | And 4 more authors.
Comptes rendus biologies | Year: 2015

In the Guianese rainforest, we examined the impact of the presence of guano in and around a bat roosting site (a cave). We used ant communities as an indicator to evaluate this impact because they occupy a central place in the functioning of tropical rainforest ecosystems and they play different roles in the food web as they can be herbivores, generalists, scavengers or predators. The ant species richness around the cave did not differ from a control sample situated 500m away. Yet, the comparison of functional groups resulted in significantly greater numbers of detritivorous fungus-growing and predatory ant colonies around the cave compared to the control, the contrary being true for nectar and honeydew feeders. The role of bats, through their guano, was shown using stable isotope analyses as we noted significantly greater δ(15)N values for the ant species captured in and around the cave compared to controls. Copyright © 2015 Académie des sciences. Published by Elsevier SAS. All rights reserved. Source

Talaga S.,French National Center for Scientific Research | Delabie J.H.C.,Upa Laboratorio Of Mirmecologia | Dezerald O.,French National Center for Scientific Research | Salas-Lopez A.,French National Center for Scientific Research | And 8 more authors.
Ecological Indicators | Year: 2015

Tank bromeliads, frequently associated with ants, are considered 'biodiversity amplifiers' for both aquatic and terrestrial organisms, and thus have a high ecological value. The focal species of this study, Aechmea aquilega, sheltered the colonies of 12 ant species in a Guianese rural habitat where Odontomachus haematodus, associated with 60% of these plants, was the most frequent. Unexpectedly, the ant species richness was higher in a compared urban habitat with 21 species, but two synanthropic and four invasive ants were noted among them. Consequently, we conducted baiting surveys (on the ground, on trees and on trees bearing A. aquilega) as well as complementary surveys using different sampling modes in urban areas to test if A. aquilega is a surrogate revealing the presence of certain invasive ants. During the baiting survey, we recorded four Neotropical and eight introduced invasive ants out of a total of 69 species. Of these 12 invasive species, five were noted by baiting A. aquilega (including two only noted in this way). A bootstrap simulation permitted us to conclude that A. aquilega significantly concentrates certain species of invasive ants. This was confirmed by complementary surveys, where we did not record further species. We conclude that baiting on trees bearing large epiphytes in human-modified, Neotropical areas is a relevant complement to the early detection of invasive ants. © 2015 Elsevier Ltd. All rights reserved. Source

Groc S.,French National Center for Scientific Research | Delabie J.H.C.,Upa Laboratorio Of Mirmecologia | Longino J.T.,Evergreen State College | Orivel J.,University Paul Sabatier | And 3 more authors.
Biological Conservation | Year: 2010

Insects, particularly ants, are good bioindicators of the state of ecosystems. Nevertheless, incorporating them into conservation surveys is expensive due to problems associated with their identification, which is exacerbated by the fact that there are fewer and fewer taxonomists working today. " Taxonomic sufficiency" (TS), which identifies organisms to a level of taxonomic resolution sufficient enough to satisfy the objectives of a study, has never been applied to Neotropical ant communities. We analysed five Neotropical datasets representing ant assemblages collected with different sampling methods in various habitats. We first treated them using two complementary and cumulative TS methods, higher-taxon and " indicator taxa" surrogacies, before testing a new approach called " mixed-level method" that combines the two previous approaches. For the higher-taxon surrogacy, we showed that, above species, genus is the most informative taxonomic level. Then, mixed-level method provided more information on ant assemblages than did the two others, even though the " indicator taxa" surrogacy was based on relevant indicator genera. Although habitat type has no effect on its efficiency, this new method is influenced by the dataset structure and the type of sampling method used to collect data. We have thus developed a new method for analyzing Neotropical ant faunas that enables the taxonomic work linked to the identification of problematic species to be significantly reduced, while conserving most of the information on the ant assemblage. This method should enhance the work of Neotropical entomologists not specialised in taxonomy, particularly those concerned with biological conservation and indication. © 2010 Elsevier Ltd. Source

Dejean A.,French National Center for Scientific Research | Dejean A.,Toulouse 1 University Capitole | Corbara B.,CNRS Microorganisms Laboratory: Genome and Environment | Corbara B.,University Blaise Pascal | And 6 more authors.
Insect Science | Year: 2015

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. © 2013 Institute of Zoology, Chinese Academy of Sciences. Source

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