16:10 - 17:10
Amphi Charles Flahault - Institute of Botany (University of Montpellier) 163 rue Auguste Broussonnet - 34000 Montpellier
Biodiversity
SESSION 3
Evolution of biodiversity over time - how have environments and organisms changed?
Paleontology and evolutionary history have helped to understand how the African environment has changed in the past and how organisms have adapted to it. This knowledge allows a prospective approach to predict risks and highlight the challenges of adaptation of organisms to current climate change.
16:10 - 16:30
We found the legs of the whales! In Senegal and Togo
Presenter: Christian Kassegne (ISEM, University of Lomo, Togo)
Christian Kassegne will present recent results from the PaleoSen and PaleonTogo projects. Two international programs which aim to discover, study and preserve the paleontological heritage of Senegal and Togo.
Several pilot expeditions have made it possible to reveal a fossiliferous potential hitherto totally unsuspected for West Africa, as well as to relaunch paleontological research in this still largely unexplored region. The continuation of this partnership will make it possible to provide irreplaceable data for understanding the evolution of modern African fauna over the long term.
16:30 - 16:50
The history of the establishment and maintenance of savannas in the forest block of Central Africa
Presenter: Karl Henga (Institute for Research in Tropical Ecology (IRET-CENAREST), Gabon) [recorded presentation and remote discussion]
The Lopé National Park (central Gabon) presents savannas included in forest formations thus giving a mosaic appearance. Fossil records reveal through pollen that extra-local vegetation (mainly Gramineae) has been present for at least 9000 years BP which indicates that these savannas are much older than their documented implementation. An opening phase around 2500 years BP saw the incursion of savannas into the forest block. This phase was contemporary with the arrival of Bantu metallurgists in the region and saw the proliferation of Elaeis guineensis, a pioneer taxon associated with human presence. Our data do not allow to conclude on an anthropogenic impact significant on the evolution of this forest-savanna mosaic. However, it seems that the absence or the documented decline of the Bantu populations between 1400 and 800 years BP was concomitant with a variation in the rainfall regime which would be at the origin of the change in tree cover in the majority of the sites with the development of pioneer taxa which invaded the savannah domain. This result suggests that the human presence in Lopé has contributed to the maintenance of the savannah enclaves.
16:50 - 17:10
The olive tree in the face of climate change: risks and challenges
Presenter: Jalal Kassout (ISEM, University of Tetouan, Morocco)
Authors: Jalal Kassout, Mohamed Ater, Jean-Frédéric Terral
1 Applied Botanical Laboratory, Bio-Agrodiversity Team, Faculty of Sciences, Abdelmalek Essaâdi University, Tetouan, Morocco.
2 Associated International Laboratory / International Research Project EVOLEA, INEE-CNRS, France - Morocco, Montpellier, France
Olive is the most iconic sclerophyllous Mediterranean tree. Nowadays, six olive subspecies are currently recognized and considered to be primary genetic resources for cultivated olive breeding. Among these subspecies, only one of them, O. europaea subsp. europaea, has been domesticated. In Morocco, olive is represented by two subspecies. The first, wild olive or oleaster, O. europaea subsp. europaea var. sylvestris, is the ancestor of the whole cultivated varieties grouped under the O. europaea subsp. europaea var. denomination sativa. The second is the Moroccan olive, O. europaea subsp. maroccana, endemic to the south-eastern part of the country. Wild olive represent a fundamental structuring element of many woody plant communities. However, its geographical distribution is highly fragmented mainly due to anthropogenic disturbances to natural habitats but amplified by climatic changes and aridification. Recently, functional approaches has made possible the identification of ecological responses of plant species to various environmental conditions, by the mean of functional traits such as leaf and wood traits. This conference explores the ecological plasticity of wild olive in Morocco in relation to variation in environmental biotic and abiotic factors. Thus, is aims to bring new insights on the resistance and vulnerability of wild forms and cultivated varieties to heterogeneous and changing environmental conditions.
All conferencescan be accessed remotely (after registration)
The experts
Christian Kassegne
Christian is a doctoral student under the supervision of Prof. C. Johnson and Dr. L. Hautier. He studies the protocols of the Middle Eocene phosphates of the coastal sedimentary basin of Togo. His research themes also focus on sedimentology, biostratigraphy and the paleoenvironmental evolution of these phosphates.
https://www.sciencedirect.com/science/article/pii/S0753396921000203?via%3Dihub
Karl Henga
Doctor in biodiversity and fossil and current ecosystem obtained at the University of Paris Sciences et Lettres and prepared at the Ecole Pratiques des Hautes Etudes (PSL-EPHE), Karl is a researcher at the Institute for Research in Tropical Ecology (IRET-CENAREST) , in Gabon. He is interested in the state of forest ecosystems in the Congo Basin and their evolution over time.
A palynologist, he mainly uses the pollen tool to assess the climatic and / or anthropogenic impact on these unstable ecosystems. Aware of the multidisciplinary approach required by his field of expertise in particular and the sciences in general, he belongs to the Global Changes team of the Institute of Evolutionary Sciences in Montpellier (ISEM).
From a more personal perspective, his wish is to see African researchers become more involved in research on the continent and he pleads for more opportunities for international collaborations made available to them.
Jalal Kassout
Jalal Kassout holds a doctorate in ecology and biodiversity from the University Abdelmalek Essaâdi (Morocco) and the University of Montpellier (France). Jalal's research focuses on the functional responses of Mediterranean trees to environmental factors, particularly drought. Currently, he is working on trees of precious importance in traditional Moroccan agroecosystems, such as the carob tree.