MADGRASS · Population Dynamics of Polyploids: Testing the Mechanisms of Grassland Expansions in Madagascar
Horizon 2020 — Marie Skłodowska-Curie Actions
- Duration
- 2022-01-10 → 2024-01-09
- EU contribution
- €224,934
- Participants
- 1
- Scheme
- MSCA-IF
Lines connect the coordinator with its partners.
Results in brief
Population Dynamics of Polyploids: Testing the Mechanisms of Grassland Expansions in Madagascar
Madagascar is considered a biodiversity hotspot and has been of much interest with respect to species conservation as well as understanding how new species arise. Approximately 65% of Madagascar is covered in grasslands, open ecosystems dominated by grasses with little tree cover. Such ecosystems occur in both the tropics and temperate regions and rose to prominence nearly eight million years ago under paleoclimate conditions of low precipitation increasing fire. However, there is uncertainty about the degree to which Madagascar’s grasslands are natural versus anthropogenic due to deforestation and the use of fire to prepare land for agriculture or grazing. This raises difficult policy questions about which areas should be targeted for reforestation tree planting programs, which grasslands should be protected for their own unique biodiversity, and which grasslands are could be exploited for economic development by rights holders. The action Population Dynamics of Polyploids: Testing the Mechanisms of Grassland Expansions in Madagascar (MADGRASS) aimed to resolve uncertainty in natural versus anthropogenic grasslands by leveraging genomic data and demographic modeling from dominant grass species. Genomes retain information about the geographic origin of populations and their changes in population size through time. However, grasses present two challenges to the application of standard computational tools that have been used for understanding the demographic history of, for example, humans. The first is that plants can be polyploids, such that they carry multiple copies of their genomes and this causes some deviations from assumptions made for existing mathematical models. The second is that grasses are often parts of hybridizing complexes, such that species may exchange genes or that their evolutionary history is complicated by historical gene flow. MADGRASS made progress on the theoretical and computational challenges of analyzing genomic data from polyploids and applied those advances towards understanding the demographic history of the focal grass species, Loudetia simplex, in Madagascar.
Data: CORDIS, © European Union
Project objective
As a consequence of anthropogenic climate change, it has been hypothesized that human-mediated deforestation degraded closed-canopy forest into grasslands dominated by fire- and grazing-resistant grasses. There is accumulating evidence, however, that tropical grasslands are natural biomes with origins that predate human activities. The extent to which grasslands have expanded and contracted in response to natural climate cycles versus more recent agricultural practices remains an open question and is the motivation for the proposed research. MADGRASS focuses on the grasslands of central Madagascar, because identifying ancient grasslands and protecting them is of urgent conservation interest. Population genomic methods and novel bioinformatic approaches will be used to test demographic hypotheses that will identify the timing of grassland expansions and contractions, population structure, and gene flow between populations. Research goals are made possible by recent advances in the analysis of polyploid species, which will be implemented through MADGRASS. There are direct conservation policy outcomes expected from MADGRASS. Currently, tree-planting programs are attempting to re-forest the grasslands of central Madagascar. These programs often include invasive tree species that grow quickly and require more water than is available, which can unintentionally lead to increased frequency and intensity of fires and overall detrimental outcomes. We will identify the range of Madagascar’s natural grasslands that should be protected. Results will also be used to identify which grasslands should be released from protected status for community and commercial use, building respect and trust with local Malagasy people. All aspects of the proposed research will be conducted in close collaboration with Malagasy colleagues and include specific outreach activities for both local communities in Madagascar and broader scientific and lay groups.
Original text from CORDIS.
Participants
- ROYAL BOTANIC GARDENS KEW · RichmondCoordinatorUnited Kingdom
Links
Data: CORDIS, © European Union