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1. Domestication Syndrome in Dacryodes edulis (Burseraceae): Comparison of Morphological and Biochemical Traits between Wild and Cultivated Populations

Author

Franca Marcelle Meguem Mboujda, Marie-Louise Avana-Tientcheu, Stéphane Takoudjou Momo, Alix Mboukap Ntongme, Virginie Vaissayre, Laura N. Azandi, Stéphane Dussert, Hilaire Womeni, Jean-Michel Onana, Bonaventure Sonké, Christopher Tankou, Jérôme Duminil, University of Dschang, Diversité, adaptation, développement des plantes (UMR DIADE), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Université de Montpellier (UM), Botanique et Modélisation de l'Architecture des Plantes et des Végétations (UMR AMAP), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-Université de Montpellier (UM), University of Yaoundé [Cameroun], Université de Yaoundé I, Université libre de Bruxelles (ULB), and ANR-16-IDEX-0006,MUSE,MUSE(2016)

Subjects
Evolutionary history, [SDV.EE.ECO]Life Sciences [q-bio]/Ecology, environment/Ecosystems, Ecology, Fruit tree species, African plum tree, Plant Science, [SDE.BE]Environmental Sciences/Biodiversity and Ecology, [SDV.BV.BOT]Life Sciences [q-bio]/Vegetal Biology/Botanics, domestication syndrome, evolutionary history, fruit tree species, non-timber forest products, [SDV.BID.SPT]Life Sciences [q-bio]/Biodiversity/Systematics, Phylogenetics and taxonomy, Domestication syndrome, Ecology, Evolution, Behavior and Systematics, Non-timber forest products
Abstract

For millennia, people have harvested fruits from the wild for their alimentation. Gradually, they have started selecting wild individuals presenting traits of interest, protecting and cultivating them. This was the starting point of their domestication. The passage from a wild to a cultivated status is accompanied by a modification of a number of morphological and genetic traits, commonly known as the domestication syndrome. We studied the domestication syndrome in Dacryodes edulis (G.Don) H.J.Lam (known as ‘African plum’ or ‘safoutier/prunier’), a socio-economically important indigenous fruit tree species in West and Central Africa. We compared wild and cultivated individuals for their sex distribution; flower, fruit and seed morphometric characteristics; seed germination temporal dynamic and fruit lipid composition. We found a higher percentage of male and male-hermaphrodite sexual types in wild populations than in cultivated ones; a lower fruit and seed mass in wild individuals; and similar mean time of germination, oil content and fatty acid composition between wild and cultivated individuals. Our results are interpreted in light of the presence of a domestication syndrome in D. edulis.

Published
2022

2. Reply to Giresse et al.: No evidence for climate variability during the late Holocene rainforest crisis in Western Central Africa

Author

Lydie M Dupont, Geoffroy de Saulieu, Yannick Garcin, Rik Tjallingii, Achim Brauer, Jean-Michel Onana, David Sebag, Pierre Deschamps, Dirk Sachse, Guillemette Ménot, Manfred R. Strecker, Enno Schefuß, Richard Oslisly, Andrew A Ako, Brian Brademann, Laura S. Epp, Kevin G Mbusnum, Institute of Earth and Environmental Science [Potsdam], University of Potsdam, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Géochimie & géochrono, Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Patrimoines Locaux et Gouvernance (PALOC), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD), Center for Marine Environmental Sciences [Bremen] (MARUM), Universität Bremen, Morphodynamique Continentale et Côtière (M2C), Centre National de la Recherche Scientifique (CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU), Department of Geosciences, University of Bremen, German Research Centre for Geosciences - Helmholtz-Centre Potsdam (GFZ), Laboratoire Chimie de l'environnement (LCE), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Faculté des Sciences - Yaoundé, Université de Yaoundé I [Yaoundé], Alfred Wegener Institute [Potsdam], Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), GeoForschungsZentrum - Helmholtz-Zentrum Potsdam (GFZ), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), Department of Geosciences [Bremen], Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC), Faculté des Sciences - Yaoundé I, Université de Yaoundé I, University of Potsdam = Universität Potsdam, Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS)

Subjects
Multidisciplinary, 010504 meteorology & atmospheric sciences, [SHS.ARCHEO]Humanities and Social Sciences/Archaeology and Prehistory, Ecology, Central africa, Climate change, Rainforest, Subtropics, 15. Life on land, Evergreen, 010502 geochemistry & geophysics, 01 natural sciences, Geography, Deciduous, 13. Climate action, [SDE]Environmental Sciences, Holocene, 0105 earth and related environmental sciences
Abstract

Giresse et al. (1) criticize both our paleoclimatic reconstruction and our inferred anthropogenic origin of the late Holocene rainforest crisis (LHRC) (2). However, their argumentation, which is combined with alleged evidence for a climatic change during the LHRC, lacks strong support. Citing studies describing both brief (weeklong) and limited periods of leaf wax production in deciduous trees, Giresse et al. (1) conclude that leaf waxes cannot record the environmental variability of a full season. However, this argument is flawed, as evergreen and subtropical deciduous trees produce leaf waxes over much longer timescales—their δD (δDwax) values have been shown to capture environmental variability on even seasonal timescales (3, 4 … [↵][1]1To whom correspondence should be addressed. Email: yannickgarcin{at}yahoo.fr. [1]: #xref-corresp-1-1

Published
2018

3. Early anthropogenic impact on Western Central African rainforests 2,600 y ago

Author

Pierre Deschamps, Brian Brademann, Dirk Sachse, Guillemette Ménot, Jean-Michel Onana, Kevin G Mbusnum, Andrew A Ako, David Sebag, Manfred R. Strecker, Enno Schefuß, Richard Oslisly, Geoffroy de Saulieu, Yannick Garcin, Laura S. Epp, Achim Brauer, Rik Tjallingii, Lydie M Dupont, Institute of Earth and Environmental Science [Potsdam], University of Potsdam = Universität Potsdam, Centre européen de recherche et d'enseignement des géosciences de l'environnement (CEREGE), Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-Collège de France (CdF (institution))-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement (LGL-TPE), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Université Jean Monnet - Saint-Étienne (UJM)-Centre National de la Recherche Scientifique (CNRS), Patrimoines Locaux et Gouvernance (PALOC), Muséum national d'Histoire naturelle (MNHN)-Institut de Recherche pour le Développement (IRD), Center for Marine Environmental Sciences [Bremen] (MARUM), Universität Bremen, Morphodynamique Continentale et Côtière (M2C), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS), German Research Centre for Geosciences - Helmholtz-Centre Potsdam (GFZ), Laboratoire Chimie de l'environnement (LCE), Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Faculté des Sciences - Yaoundé I, Université de Yaoundé I, Alfred Wegener Institute [Potsdam], Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), GeoForschungsZentrum - Helmholtz-Zentrum Potsdam (GFZ), University of Potsdam, Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Collège de France (CdF)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), Laboratoire de Géologie de Lyon - Terre, Planètes, Environnement [Lyon] (LGL-TPE), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-École normale supérieure - Lyon (ENS Lyon), Centre National de la Recherche Scientifique (CNRS)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Caen Normandie (UNICAEN), Normandie Université (NU), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), Faculté des Sciences - Yaoundé, Université de Yaoundé I [Yaoundé], Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Collège de France (CdF (institution))-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Recherche Agronomique (INRA), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU)-Institut de Chimie du CNRS (INC), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)

Subjects
010506 paleontology, 010504 meteorology & atmospheric sciences, Drainage basin, Climate change, Rainforest, medicine.disease_cause, paleohydrology, Western Central Africa, 01 natural sciences, rainforest crisis, Pollen, medicine, Ecosystem, ddc:911, 0105 earth and related environmental sciences, geography, Multidisciplinary, geography.geographical_feature_category, business.industry, Ecology, Fragmentation (computing), Vegetation, human activity, 15. Life on land, late Holocene, 13. Climate action, Agriculture, [SDU]Sciences of the Universe [physics], Institut für Geowissenschaften, business
Abstract

(IF 9.58; Q1); International audience; A potential human footprint on Western Central African rainforests before the Common Era has become the focus of an ongoing controversy. Between 3,000 y ago and 2,000 y ago, regional pollen sequences indicate a replacement of mature rainforests by a forest–savannah mosaic including pioneer trees. Although some studies suggested an anthropogenic influence on this forest fragmentation, current interpretations based on pollen data attribute the ‘‘rainforest crisis’’ to climate change toward a drier, more seasonal climate. A rigorous test of this hypothesis, however, requires climate proxies independent of vegetation changes. Here we resolve this controversy through a continuous 10,500-y record of both vegetation and hydrological changes from Lake Barombi in Southwest Cameroon based on changes in carbon and hydrogen isotope compositions of plant waxes. δ13C-inferred vegetation changes confirm a prominent and abrupt appearance of C4 plants in the Lake Barombi catchment, at 2,600 calendar years before AD 1950 (cal y BP), followed by an equally sudden return to rainforest vegetation at 2,020 cal y BP. δD values from the same plant wax compounds, however, show no simultaneous hydrological change. Based on the combination of these data with a comprehensive regional archaeological database we provide evidence that humans triggered the rainforest fragmentation 2,600 y ago. Our findings suggest that technological developments, including agricultural practices and iron metallurgy, possibly related to the large-scale Bantu expansion, significantly impacted the ecosystems before the Common Era.

Published
2018

4. A combined analysis of morphological traits, chloroplast and nuclear DNA sequences within Santiria trimera (Burseraceae) suggests several species following the Biological Species Concept

Author

Charles Doumenge, Olivier J. Hardy, Kouamé Guillaum Koffi, Myriam Heuertz, Jean Michel Onana, Frederick Gavory, Faculté des Sciences, Evolutionary Biology and Ecology, Université libre de Bruxelles (ULB), Centre of Forest Research, Partenaires INRAE, Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Herbier National du Cameroun, and Bayer Cropscience

Subjects
0106 biological sciences, Sympatry, Phylogénie, Speciation, [SDV]Life Sciences [q-bio], ADN, Évolution, Plant Science, F50 - Anatomie et morphologie des plantes, 01 natural sciences, F30 - Génétique et amélioration des plantes, Espèce, Monophyly, Séquence d'ADN, Santiria, Forêt tropicale humide, Phylogeny, 0303 health sciences, education.field_of_study, Phylogenetic tree, biology, Ecology, F70 - Taxonomie végétale et phytogéographie, Reproductive isolation, Sympatric speciation, ADN chloroplastique, Burseraceae, Rainforest, Morphotype, Population, Allopatric speciation, 010603 evolutionary biology, 03 medical and health sciences, Biotype, parasitic diseases, education, 030304 developmental biology, Morphologie végétale, Biologie moléculaire, 15. Life on land, biology.organism_classification, Evolutionary biology
Abstract

International audience; Background and aims Species delimitation remains a difficult task in many groups of organisms. Even widespread and conspicuous tropical trees make no exception. Santiria trimera, an African rainforest tree, displays substantial morphological variability. While classical analysis of historical herbarium samples lead to the recognition of a single species, two morphotypes of S. trimera are regularly collected in Gabon and Equatorial Guinea, sometimes in sympatry: one form with stilt roots (SR) and another form without stilt roots (NSR). Methods To assess whether these forms constitute distinct taxa and to understand evolutionary processes within African Santiria, we combined a morphological and a spatial analysis of both sympatric morphotypes in northern Gabon with a phylogenetic analysis of samples from West and Central Africa, including the island of Sao Tome. Key results In Gabon, morphological traits, chloroplast DNA (cpDNA) and nuclear DNA (nuDNA) sequences congruently lead to the recognition of two well differentiated and reproductively isolated taxa corresponding to SR and NSR morphotypes. However, rare cases of the SR morphotype bearing DNA sequences typical of NSR individuals suggest that hybridization might sometimes occur. No evidence for habitat specialization of the two taxa was found. DNA sequences from Sao Tome formed monophyletic clades at both marker types and the nuDNA gene tree suggests that the Sao Tome population probably originated from Central Africa and subsequently underwent allopatric differentiation from continental populations. Conclusion In Central Africa, S. trimera is composed of at least two distinct sympatric species following the Biological Species Concept and calls for further morphological and phenological studies and experimental crosses between them to specify their taxonomic status. Our results also show that classical taxonomic species delimitation may not always be congruent with the Biological Species Concept, calling for more population-based in situ morphological and molecular genetic analyses.

Published
2010

5. Socio-cultural importance, economic and therapeutic potential of Carapa (Meliaceae) in Senegal

Author

Gueye, Mathieu, Kenfack, David, Forget, Pierre-Michel, Institut Fondamental d'Afrique Noire (IFAN), Université Cheikh Anta Diop [Dakar, Sénégal] (UCAD), Smithsonian Tropical Research Institute, Mécanismes adaptatifs : des organismes aux communautés, Muséum national d'Histoire naturelle (MNHN)-Centre National de la Recherche Scientifique (CNRS), Xander van der Burgt, Jos van der Maesen, Jean-Michel Onana, and FORGET, Pierre-Michel

Subjects
[SDV.EE]Life Sciences [q-bio]/Ecology, environment, [SDV.EE] Life Sciences [q-bio]/Ecology, environment, Afrique, Sénégal, potentialités économiques et thérapeutiques, [SDV.BV]Life Sciences [q-bio]/Vegetal Biology, [SDV.BV] Life Sciences [q-bio]/Vegetal Biology, [SDV.BID]Life Sciences [q-bio]/Biodiversity, [SDV.BID] Life Sciences [q-bio]/Biodiversity, Carapa, importance socio-culturelle
Abstract

Carapa species are trees and shrubs of tropical forests. In Africa, although Carapa species are widely distributed and diversified from Senegal to Rwanda, their commercial exploitation remains restricted despite their known domestic uses. In Senegal, Carapa is most abundant in Mid and lower Casamance and in the gallery forests of East Senegal. Carapa species are recognised for socio-cultural or medicinal importance throughout their area of distribution.Traditionally the oil is extracted by women in menopause and is used to treat dozens of illnesses and in cosmetics. Leaves, bark and roots are also used., Les Carapa sont des arbres et arbustes des forêts tropicales. En Afrique, si les Carapa sont largement distribués et diversifiés du Sénégal au Rwanda, leur exploitation commerciale demeure cependant embryonnaire malgré des usages domestiques reconnus. Au Sénégal les Carapa sont plus abondants en moyenne et basse Casamance et dans les galeries forestières des savanes du Sénégal oriental. Les Carapa sont d'importance socio-culturelle ou médicinale reconnue sur toute leur aire de distribution. L'huile est traditionnellement extraite par les femmes ménopausées et est utilisée dans le traitement d'une dizaine de maladies et en cosmétique. Les feuilles, les écorces et les racines sont également utilisées.

Published
2010

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