Format: ORAL

Shengwei Wang1,2, Neng Wei1,2, Tao Wang1,2, Qingfeng Wang1,2

1 Wuhan Botanical Garden, Chinese Academy of Sciences; 2 Sino-Africa Joint Research Center, Chinese Academy of Sciences.

The East African mountains are one of the worlds crucial biodiversity hotspots, and their distinctivesky island structure makes them a Garden of Eden for the evolution of plant diversity.Long-term studies have focused on the diversity and evolution of the Afroalpine flora, and there is a lack of research on the floristic history of the entire montane system.Recent plant catalogs from East African mountainsreveal the extremely high diversity of plants here, with about 7,000 speciesin 193 families and 1,544 genera, of whichmore than 15%are endemic to East Africa.The spatial and temporal phylogenetic patterns of the mountain flora reveal that the East African mountains are a convergence of ancient and young plants,serving as a museum and cradle of plant diversity in East Africa.Habitat disturbances caused by Pleistocene climate oscillations have led to colonization, dispersion, extinction, and evolution of species.Especially the dispersal of habitats of montane forest species to intervening lowlands during the Pleistocene glacial period facilitated species exchange between mountains.Meanwhile,the temporal differences in mountainous geological dynamics, such as volcanism and uplift, coupled with the island effect, intensify the differentiation of populations among mountains.Our research shows that the East African mountains are experiencing a gradual upward trend in the number of exotic plants, which poses a serious problem of homogenization of native plants. Plant diversity in the East African mountains faces vulnerability and urgently needs more conservation and research attention.