Abstract: Five polymorphic microsatellite loci of the arboreal ant Allomerus decemarticulatus (Myrmicinae) were isolated and characterized. The amplification and polymorphism of seven additional microsatellite loci, previously developed for the ant species A. octoarticulatus and Wasmannia auropunctata, were also tested and the amplification conditions necessary for genotyping the complete set of 12 multiplexed markers in A. decemarticulatus determined. The number of alleles per locus ranged from three to 15 and observed heterozygosity varied front 0.09 to 0.95. Cross-species amplification of these loci was also successfully achieved in additional species of the same ant subfamily, Myrmicinae. This set of microsatellite markers will be used in studies on the mating system and population genetic structure of Myrmicinae in general and A. decemarticulatus in particular.

Abstract: Nucleotide diversity was assessed within nine candidate genes (in total 4.6 kb) for the time of bud burst in nine sessile oak (Quercus petraea) populations distributed in central and northern Europe. The sampled populations were selected on the basis of their contrasting time of bud burst observed in common garden experiments (provenance tests). The candidate genes were selected according to their expression profiles during the transition from quiescent to developing buds and/or their functional role in model plants. The overall nucleotide diversity was large (pi(tot) – 6.15 x 10(-3); pi(silent) – 11.2 x 10(-3)), but population differentiation was not larger than for microsatellites. No outlier single-nucleotide polymorphism (SNP), departing from neutral expectation, was found among the total of 125 SNPs. These results contrasted markedly with the significant associations that were observed between the candidate genes and bud burst in segregating populations. Quantitative trait loci (QTLs) for bud burst were identified for 13 year*site seasonal observations in a cloned mapping pedigree. Nineteen QTLs were detected, and QTLs located on linkage groups 2, 5 and 9 contributed repeatedly to more than 12% of the phenotypic variation of the trait. Eight genes were polymorphic in the two parents of the pedigree and could be mapped on the existing genetic map. Five of them located within the confidence intervals of QTLs for bud burst. Interestingly, four of them located within the three QTLs exhibiting the largest contributions to bud burst. Heredity (2010) 105, 401-411; doi:10.1038/hdy.2009.170; published online 9 December 2009

Abstract: P>1. Modelling growth strategies among tropical trees is an important objective in predicting the response of tree dynamics to selective logging and in gaining insights into the ecological processes that structure tree communities in managed tropical forests. 2. We developed a disturbance index to model the effects of distance to and area of logging gaps on stem radial growth rates. This index was tested using census data of 43 neotropical tree species, representing a variety of life-history strategies and developmental stages, from a selectively logged forest at Paracou, French Guiana. Growth strategies were analyzed in light of two indicators: the inherent species growth rate (when disturbance index is null) and the species reaction (change in growth rate) to logging gaps. 3. Across species, the predicted inherent growth rates in unlogged forest ranged from 0 center dot 25 to 6 center dot 47 mm year-1, with an average growth of 2 center dot 29 mm year-1. Ontogenetic shifts in inherent growth rate were found in 26 of the 43 species. 4. Species growth response to logging gaps varied widely among species but was significantly positive for 27 species. The effect of ontogeny on growth response to logging was retained for 14 species, and species with inherent fast growth rate (5 mm year-1) responded less to logging gap disturbances than did species with slow inherent growth (1 mm year-1). 5. Functional traits explained 19-42% of the variation in the inherent growth rate and in species' response across all developmental stages. Whereas maximum diameters and seed mass were strong predictors of inherent growth rate, maximum height, wood density, mode of germination and stem architecture were additionally involved in tree growth response. 6. Synthesis and applications: This study provides a necessary framework for developing predictive post-logging growth models for the thousands of species comprising tropical forests and is sufficiently general to apply to a broad range of managed tropical forests.

Abstract: We examined fine-scale heterogeneity of environmental conditions in a primary rain forest in French Guiana to describe variation in microhabitats that plants may experience during establishment. We characterized both the range as well as the spatial structuring of 11 environmental factors important for seedling establishment in six hexagonal sampling grids, one each in gap and understory sites at three points representing the predominant geomorphic units in this primary forest. Each grid contained 37 sampling points separated by 31 cm-20 m. Monte-Carlo tests of semivariograms against complete spatial randomness indicated that for many variables in all six sampling grids, spatial dependence did not exceed 1 m. A principal component analysis of all sampling points revealed a lack of spatial microhabitat structure, rather than homogeneous patches associated with canopy structure or geomorphology. Our results suggest that ample fine-scale spatial heterogeneity exists to support the coexistence of plant species with differential abiotic requirements for regeneration.

Abstract: The origin and timing of the appearance of leaf domatia during the ontogeny of plants are important evolutionary traits driving the maintenance of ant-plant associations. In this study conducted in French Guiana on Hirtella physophora, Maieta guianensis, and Tococa guianensis, we focused on the formation and development of leaf domatia having different morphological origins. We modeled the timing of the onset of these domatia, then compared their morpho-anatomical structure. Although the ontogenetic development of the domatia differed between species, they developed very early in the plant's ontogeny so that we did not note differences in the timing of the onset of these domatia. For H. physophora seedlings, a transitional leaf forms before the appearance of fully developed domatia, whereas in M. guianensis and T. guianensis the domatia forms abruptly without transitional leaves. Moreover, in all cases, the morpho-anatomical structure of the domatia differed considerably from the lamina. All three species had similar morpho-anatomical characteristics for the domatia, indicating a convergence in their structural and functional characteristics. This convergence between taxonomically distant plant species bearing domatia having different morphological origins could be interpreted as a product of the plant's evolution toward the morphology and anatomy most likely to maximize ant recruitment and long-term residence.