Abstract Detail



Biogeography

Lingyun, Chen [1], Guangwan, Hu [1], Qingfeng, Wang [1].

Phytogeography of major alpine plants in East Africa.

East Africa is a crucial biodiversity hotspot on earth. The area is characterized by elevated plateaus and isolated mountains in Ethiopia, Uganda, Kenya, and Tanzania. Although dozens of studies have investigated plant phylogeography patterns in East Africa, only a few studies have investigated the phylogeography of Afro-alpine plants. During past eight years, we have carried out fieldwork in East Africa mountains, in order to get preliminary data and samples to explore diversity and phytogeography of alpine plants. Here we studied the phylogeography of Haplocarpha rueppelii (Asteraceae) in East Africa. Our results show that this species consists of two major groups, one includes the populations from Mts. Elgon, Aberdare and Bale, while the other includes Mts. Kenya and Kilimanjaro. Also, we show that H. rueppellii colonized Mts. Kenya and Aberdare during the Pleistocene. However, migration rate for individuals between the two mountains was low as showed by gene flow analysis, suggesting a barrier for plant dispersal and gene flow between Mts. Aberdare and Kenya since the Pleistocene. Furthermore, in order to study biogeographic origin of the famous African giant lobelias, we reconstructed the phylogenetic relationships of Lobelioideae. Our results show that the ancestor of African giant lobelias arrived from Asia. Additionally, we found that giant lobelias from Asia, Africa and South America show convergent evolution of gigantism. We also explored the molecular mechanisms of adaptation to different altitudes in Lobelia. We used RNA-seq data of a middle-altitude species, L. aberdarica, and the high-altitude species L. telekii. We identified several genes that are potentially involved in DNA repair, response to DNA damage and temperature stimulus, and regulation of gene expression. These finding could suggest how giant lobelias adapt to high altitudinal environment that characterized by cold, low oxygen, and strong ultraviolet radiation. Next, we will study phylogeogaphy of the other major alpine groups such as Dendrosenecio and Lobelia to investigate effects of major geographic factors such as East Rift Valley and possible migration corridor(s) on alpine plants. 


1 - Chinese Academy of Sciences, Sino-Africa Joint Research Center, Jiufeng No. 1 Road, Wuhan, 430074, China

Keywords:
Afro-alpine plants
Biogeography.

Presentation Type: Poster
Number: PBG004
Abstract ID:527
Candidate for Awards:None


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