Central AFrican Rain fOrests: past DYNamics and future resilience (AFRODYN)

Programme : ANR - Programme Jeunes Chercheuses et Jeunes Chercheurs (JCJC)
Durée : 2015 - 2017

Mots clés

African biodiversity, genetic diversity datasets, gene flow corridors, next generation sequencing, phylogeographic patterns, species distribution modeling

Résumé

Species are going extinct at an unprecedented rate. This extinction is largely associated with global changes from land use to climate variation. Tropical rain forests (TRFs) harbor high diversity, representing 50% of terrestrial species biodiversity on just 10% of the land. Moreover, TRF provide vital ecosystem services and are also considered important global climate regulators. A better understanding of past dynamics and future resilience of TRF will provide vital information for pinpointing conservation strategy priorities and help management of TRF.

The current project will focus on the TRFs of Central Africa where the local diversity is thought to be highly threatened. The main questions we address are: How have species been able to adapt to past change? How will genetic diversity within species be affected by ongoing climate change? In this project, we plan to answer these questions using a multispecies approach and an unprecedented genetic dataset for African plant species. Our objectives will be to 1) test different hypotheses of Central African rain forests dynamics in the past within and between species and 2) infer the potential resilience of this ecosystem to future climate change.

To do so, a comparative phylogeography approach combined with species distribution modeling will be undertaken simultaneously on six co-distributed plant species in Central Africa and belonging to two model rain forest restricted plant families: Annonaceae and palms. These species combine several important features facilitating the project: easily identifiable in the field; characteristic and common across Central African TRFs and; availability of good preliminary data. For all sampled individuals (~660) we will sequence full plastomes and about one hundred nuclear markers using NGS. We will link past genetic dynamics with estimated climatically stable areas inferred by paleoclimatic modeling. Preliminary results indicate that for at least one species of palms, inferred climatically stable areas are congruent with high and unique genetic diversity in Central Africa. Future species distributions will be integrated with current genetic diversity knowledge to generate heat maps of threatened and high priority areas for conservation. Results of the project will greatly improve our understating of rain forest evolution and its response to ongoing climate change.

This study will be of value to the fields of evolutionary biology, conservation biology and management as well as human evolutionary history. AFRODYN is unique in that it will use methods from an array of interdisciplinary fields integrating paleo and future climatic modeling, ecology, molecular biology and population genetics. Such an approach will set the stage for a better region-wide understanding of the threats to African rain forest biodiversity and the regions of high conservation priority.

Collaborations

  • IRD (UMR AMAP, UMR DIADE)
  • CNRS
  • Centre d'Ecologie Fonctionnelle et Evolutive (CEFE)
  • Université Libre de Bruxelles (Belgique)
  • Université de Yaoundé 1 (Cameroun)