Macroevolutionary insights into sedges (Carex: Cyperaceae): The effects of rapid chromosome number evolution on lineage diversification  

作　　者：José I.Márquez-Corro Santiago Martín-Bravo Pedro Jiménez-Mejías Andrew L.Hipp Daniel Spalink Robert F.C.Naczi Eric H.Roalson Modesto Luceño Marcial Escudero 

机构地区：[1]Department of Molecular Biology and Biochemical Engineering,Universidad Pablo de Olavide,Carretera de Utrera km 1,Seville ES 41013,Spain [2]Departamento de Biología(Botánica),Facultad de Ciencias Biológicas,Universidad Autónoma de Madrid,c/Darwin 2,Madrid 28049,Spain [3]The Morton Arboretum,4100 Illinois Route 53,Lisle,IL 60532,USA [4]The Field Museum,Integrative Research Center,1400S Lake Shore Dr,Chicago,IL 60605,USA [5]Department of Ecology and Conservation Biology,Texas A&M University,College Station,TX 77843,USA [6]New York Botanical Garden,2900 Southern Boulevard,Bronx,NY 10458-5126,USA [7]School of Biological Sciences,Washington State University,Pullman,WA 99164-4236,USA [8]Department of Plant Biology and Ecology,University of Seville,Reina Mercedes sn,Seville ES 41012,Spain

出　　处：《Journal of Systematics and Evolution》2021年第4期776-790,共15页植物分类学报（英文版）

基　　金：support from the Spanish Ministry of Economy and Competitiveness through a research project to ML and SM-B(CGL2016-77401-P),to ME(PGC2018-099608-B-I00);a Ph.D.scholarship to JIM-C(BES-2017-079621).

摘　　要：Changes in holocentric chromosome number due to fission and fusion have direct and immediate effects on genome structure and recombination rates.These,in turn,may influence ecology and evolutionary trajectories profoundly.Sedges of the genus Carex(Cyperaceae)comprise ca.2000 species with holocentric chromosomes.The genus exhibits a phenomenal range in the chromosome number(2n=10−132)with almost not polyploidy.In this study,we integrated the most comprehensive cytogenetic and phylogenetic data for sedges with associated climatic and morphological data to investigate the hypothesis that high recombination rates are selected when evolutionary innovation is required,using chromosome number evolution as a proxy for recombination rate.We evaluated Ornstein-Uhlenbeck models to infer shifts in chromosome number equilibrium and selective regime.We also tested the relationship between chromosome number and diversification rates.Our analyses demonstrate significant correlations between morphology and climatic niche and chromosome number in Carex.Nevertheless,the amount of chromosomal variation that we are able to explain is very small.We recognized a large number of shifts in mean chromosome number,but a significantly lower number in climatic niche and morphology.We also detected a peak in diversification rates near intermediate recombination rates.In combination,these analyses point toward the importance of chromosome evolution to the evolutionary history of Carex.Our work suggests that the effect of chromosome evolution on recombination rates,not just on reproductive isolation,may be central to the evolutionary history of sedges.

关 键 词：BAYOU bioclimatic variables Brownian motion DIVERSIFICATION morphological characters Ornstein-Uhlenbeck model Phylogenetic Comparative Methods QuaSSE SLOUCH 

分 类 号：Q94[生物学—植物学]