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Barthe S, Binelli G, Hérault B, Scotti-Saintagne C, Sabatier D, Scotti I. Tropical rainforests that persisted: inferences from the Quaternary demographic history of eight tree species in the Guiana shield. Mol Ecol 2017; 26:1161-1174. [PMID: 27926985 DOI: 10.1111/mec.13949] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2016] [Revised: 11/14/2016] [Accepted: 11/15/2016] [Indexed: 11/29/2022]
Abstract
How Quaternary climatic and geological disturbances influenced the composition of Neotropical forests is hotly debated. Rainfall and temperature changes during and/or immediately after the last glacial maximum (LGM) are thought to have strongly affected the geographical distribution and local abundance of tree species. The paucity of the fossil records in Neotropical forests prevents a direct reconstruction of such processes. To describe community-level historical trends in forest composition, we turned therefore to inferential methods based on the reconstruction of past demographic changes. In particular, we modelled the history of rainforests in the eastern Guiana Shield over a timescale of several thousand generations, through the application of approximate Bayesian computation and maximum-likelihood methods to diversity data at nuclear and chloroplast loci in eight species or subspecies of rainforest trees. Depending on the species and on the method applied, we detected population contraction, expansion or stability, with a general trend in favour of stability or expansion, with changes presumably having occurred during or after the LGM. These findings suggest that Guiana Shield rainforests have globally persisted, while expanding, through the Quaternary, but that different species have experienced different demographic events, with a trend towards the increase in frequency of light-demanding, disturbance-associated species.
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Affiliation(s)
- Stéphanie Barthe
- UMR EcoFoG ("Ecologie des forêts de Guyane"), UAG, Campus Agronomique, BP 709, 97387, Kourou, French Guiana.,UMR EcoFoG ("Ecologie des forêts de Guyane"), INRA, Campus Agronomique, BP 709, 97387, Kourou, French Guiana
| | - Giorgio Binelli
- DBSV ("Dipartimento di Biotecnologie e Scienze della Vita"), Università degli Studi dell'Insubria, via J.H. Dunant 3, 21100, Varese, Italy
| | - Bruno Hérault
- UMR EcoFoG ("Ecologie des forêts de Guyane"), CIRAD, Campus Agronomique, BP 709, 97387, Kourou, French Guiana
| | - Caroline Scotti-Saintagne
- URFM ("Écologie des Forêts Méditerranéennes"), INRA, Domaine Saint_Paul, Site Agroparc, 84914, Avignon, France
| | - Daniel Sabatier
- UMR AMAP ("Botanique et modélisation de l'architecture des plantes et des végétations"), IRD, Boulevard de la Lironde, Parc Scientifique 2, 34398, Montpellier, France
| | - Ivan Scotti
- URFM ("Écologie des Forêts Méditerranéennes"), INRA, Domaine Saint_Paul, Site Agroparc, 84914, Avignon, France
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Relationships between demography and gene flow and their importance for the conservation of tree populations in tropical forests under selective felling regimes. CONSERV GENET 2009. [DOI: 10.1007/s10592-009-9983-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Latouche-Hallé C, Ramboer A, Bandou E, Caron H, Kremer A. Long-distance pollen flow and tolerance to selfing in a neotropical tree species. Mol Ecol 2004; 13:1055-64. [PMID: 15078444 DOI: 10.1111/j.1365-294x.2004.02127.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Outcrossing rates, pollen dispersal and male mating success were assessed in Dicorynia guianensis Amshoff, a neotropical tree endemic to the Guiana shield. All adult trees within a continuous area of 40 ha (n = 157) were mapped, and were genotyped with six microsatellite loci. In addition, progenies were genotyped from 22 mature trees. At the population level, the species was mostly outcrossing (tm = 0.89) but there was marked variation among individuals. One tree exhibited mixed mating, confirming earlier results obtained with isozymes that D. guianensis can tolerate selfing. A Bayesian extension of the fractional paternity method was used for paternity analysis, and was compared with the neighbourhood method used widely for forest trees. Both methods indicated that pollen dispersal was only weakly related to distance between trees within the study area, and that the majority (62%) of pollen came from outside the study stand. Using maximum likelihood, male potential population size was estimated to be 1119, corresponding to a neighbourhood size of 560 hectares. Male mating success was, however, related to the diameter of the stem and to flowering intensity assessed visually. The mating behaviour of D. guianensis is a combination of long-distance pollen flow and occasional selfing. The species can still reproduce when it is extremely rare, either by selfing or by dispersing pollen at long distances. These results, together with the observation that male mating success was correlated with the size of the trees, could be implemented in management procedures aiming at regenerating the species.
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Affiliation(s)
- C Latouche-Hallé
- INRA UMR BIOGECO, Biodiverity, Genes & Ecosystems, 69, route d'Arcachon 33610-Cestas, France
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Latouche-Hallé C, Ramboer A, Bandou E, Caron H, Kremer A. Nuclear and chloroplast genetic structure indicate fine-scale spatial dynamics in a neotropical tree population. Heredity (Edinb) 2003; 91:181-90. [PMID: 12886285 DOI: 10.1038/sj.hdy.6800296] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Dicorynia guianensis is a canopy tree, endemic to the tropical rain forest of French Guiana. We compared generational and spatial genetic structure for maternally and biparentally inherited markers in two cohorts (adult and seedling) in order to infer processes shaping the distribution of genetic diversity. The study was conducted on a 40 ha study plot located at Paracou near Kourou, where 172 adults trees and 375 saplings were sampled. Aggregation of trees was therefore suggested at different distances, ranging from 100 to 400 m. There was a strong link between demographic and genetic spatial structures at small distances (less than 100 m) that is likely to be the consequence of restricted seed dispersal. Genetic differentiation was more pronounced between spatial aggregates than between cohorts. Despite the spatial differentiation, the species was able to maintain high levels of diversity for maternal genomes, suggesting rapid turnover of aggregates. Spatial autocorrelation was larger for chloroplast than nuclear markers indicating a strong asymmetry between pollen and seed flow. Fixation indices indicated a lower heterozygote deficiency for the adults, maybe because of gradual elimination of selfed trees. Genetic relatedness at lower distances was higher in adult trees than in saplings, as a result of generation overlapping in the adult cohort. Overall, our results confirm earlier biological knowledge about the dispersion mechanisms of the species, and lead to an enhanced role of spatial processes in the dynamics of genetic diversity of D. guianensis.
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Affiliation(s)
- C Latouche-Hallé
- INRA Station de Recherches Forestières, Laboratoire de Génétique des Arbres Forestiers BP45, 33611 Gazinet, France
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Squirrell J, Hollingsworth PM, Woodhead M, Russell J, Lowe AJ, Gibby M, Powell W. How much effort is required to isolate nuclear microsatellites from plants? Mol Ecol 2003; 12:1339-48. [PMID: 12755865 DOI: 10.1046/j.1365-294x.2003.01825.x] [Citation(s) in RCA: 237] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The attributes of codominance, reproducibility and high resolution have all contributed towards the current popularity of nuclear microsatellites as genetic markers in molecular ecological studies. One of their major drawbacks, however, is the development phase required to obtain working primers for a given study species. To facilitate project planning, we have reviewed the literature to quantify the workload involved in isolating nuclear microsatellites from plants. We highlight the attrition of loci at each stage in the process, and the average effort required to obtain 10 working microsatellite primer pairs.
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Affiliation(s)
- J Squirrell
- Royal Botanic Garden Edinburgh, 20 A Inverleith Row, Edinburgh, EH3 5LR, UK.
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