Abstract Detail



Biogeography

Yan, Yujing [1], Davis, Charles [2], Wang, Zhiheng [3], Rahbek, Carsten [4], Borregaard, Michael [5].

Amphi-Pacific Tropical Disjunction of Theaceae: Multiple Intercontinental Dispersals Corresponding to Changing Climate .

Two alternative hypotheses explaining the tropical intercontinental disjunctions are that plants dispersed between Old and New Worlds through the boreotropical forest during the early Cenozoic, or that the dispersal was mainly a function of the area of the source and sink biomes (long-distance dispersal). However, it remains difficult to distinguish between these hypotheses as more informative fossil records are lacking and the tropical taxa were removed from high latitude region. Here, we used tea plants (Theaceae family) as a model group and integrated phylogenetic, paleontological and climatic data to understand the ecological and evolutionary process underlying such unique distribution pattern.
We sampled 58% of the currently accepted Theaceae species across the world. A time-calibrated phylogeny was generated based on plastid and nuclear ribosomal DNA sequence data to infer the evolutionary history of the family. We reconstructed ancestral range and habitat at node using DEC model and stochastic character mapping method, and inferred the dispersal, preservation and extinction rate for different regions using time-stratified DES model based on fossil records.  
We found that the New World species do not form monophyletic lineages, indicating that there are multiple dispersal events between Old World and New World across the phylogeny. Both boreotropical migration and long-distance dispersal contribute to the current distribution pattern of Theaceae. The dispersal correlates with changing temperature and the range size of ancestral habitat. Theaceae probably originated in Eurasia, and was part of the Boreotropical vegetation.


1 - 345 Franklin St, Cambridge, MA, 02139, United States
2 - Harvard University Herbaria, Organismic and Evolutionary Biology, 22 Divinity Avenue, Cambridge, Massachusetts, 02138, United States
3 - Peking University, Beijing, CHN
4 - University of Copenhagen, Center for Macroecology, Evolution and Climate Change, , Copenhagen, Denmark
5 - Center for Macroecology, Evolution and Climate Change, Copenhagen, Denmark

Keywords:
Boreotropical
long distance dispersal
Disjunctive distribution.

Presentation Type: Poster
Number: PBG005
Abstract ID:559
Candidate for Awards:None


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