国际著名期刊美国《国家科学院院刊》（PNAS）2月19日在线发表了中国科学院武汉植物园王恒昌博士和美国佛罗里达大学合作研究的研究论文：Rosid radiation and the rapid rise of angiosperm-dominated forests。
现存大约30万种的被子植物，分为约15,000属和400多科。理解这些类群的亲缘关系是一个艰巨的任务。本项研究通过多取样、多基因的策略，并采用基因序列同时比对可信的化石记录的方法开展研究。结果表明，现存约三十万种显花植物的1/3组成的一个谱系，即Rosids（蔷薇类）在9千万年前曾经历了一次爆发式分化，同时又引发了两栖类、蚂蚁、哺乳动物、蕨类等类群的适应辐射式物种形成。该研究利用现存生物的分子证据，首次揭示了这些植物的进化关系，为它们的快速形成和分化提供了依据。文章揭示出在一次爆发式分化中显花植物的分化，形成了以被子植物为主体的森林系统，这些森林系统后来成为了各种有机体的栖息地。研究结果对认识地球上生物类群间的亲缘关系，以及理解特定空间区域内物种的相互竞争关系也具有十分重要的指导意义。(生物谷Bioon.com)
生物谷推荐原始出处：
PNAS，doi: 10.1073/pnas.0813376106，Hengchang Wang，Douglas E. Soltis
Rosid radiation and the rapid rise of angiosperm-dominated forests
Hengchang Wanga,b, Michael J. Moorec, Pamela S. Soltisd, Charles D. Belle, Samuel F. Brockingtonb, Roolse Alexandreb, Charles C. Davisf, Maribeth Latvisb,f, Steven R. Manchesterd and Douglas E. Soltisb,1
aWuhan Botanical Garden, The Chinese Academy of Science, Wuhan, Hubei 430074 China;
bDepartment of Botany and
dFlorida Museum of Natural History, University of Florida, Gainesville, FL 32611;
cBiology Department, Oberlin College, Oberlin, OH 44074-1097;
eDepartment of Biological Sciences, University of New Orleans, New Orleans, LA 70148; and
fDepartment of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138
Abstract
The rosid clade (70,000 species) contains more than one-fourth of all angiosperm species and includes most lineages of extant temperate and tropical forest trees. Despite progress in elucidating relationships within the angiosperms, rosids remain the largest poorly resolved major clade; deep relationships within the rosids are particularly enigmatic. Based on parsimony and maximum likelihood (ML) analyses of separate and combined 12-gene (10 plastid genes, 2 nuclear; >18,000 bp) and plastid inverted repeat (IR; 24 genes and intervening spacers; >25,000 bp) datasets for >100 rosid species, we provide a greatly improved understanding of rosid phylogeny. Vitaceae are sister to all other rosids, which in turn form 2 large clades, each with a ML bootstrap value of 100%: (i) eurosids I (Fabidae) include the nitrogen-fixing clade, Celastrales, Huaceae, Zygophyllales, Malpighiales, and Oxalidales; and (ii) eurosids II (Malvidae) include Tapisciaceae, Brassicales, Malvales, Sapindales, Geraniales, Myrtales, Crossosomatales, and Picramniaceae. The rosid clade diversified rapidly into these major lineages, possibly over a period of <15 million years, and perhaps in as little as 4 to 5 million years. The timing of the inferred rapid radiation of rosids [108 to 91 million years ago (Mya) and 107–83 Mya for Fabidae and Malvidae, respectively] corresponds with the rapid rise of angiosperm-dominated forests and the concomitant diversification of other clades that inhabit these forests, including amphibians, ants, placental mammals, and ferns.
