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Temperate South American–Asian disjunct distributions are the most unusual in organisms, and challenging to explain. Here, we address the origin of this unusual disjunction in Lardizabalaceae using explicit models and molecular data. The family (c.40 species distributed in ten genera) also provides an opportunity to explore the historical assembly of East Asian subtropical evergreen broadleaved forests, a typical and luxuriant vegetation in East Asia. DNA sequences of five plastid loci of 42 accessions representing 23 species of Lardizabalaceae (c. 57.5% of estimated species diversity), and 19 species from the six other families of Ranunculales, were used to perform phylogenetic analyses. By dating the branching events and reconstructing ancestral ranges, we infer that extant Lardizabalaceae dated to the Upper Cretaceous of East Asia and that the temperate South American lineage might have split from its East Asian sister group at c. 24.4 Ma. A trans‐Pacific dispersal possibly by birds from East Asia to South America is plausible to explain the establishment of the temperate South American–East Asian disjunction in Lardizabalaceae. Diversification rate analyses indicate that net diversification rates of Lardizabalaceae experienced a significant increase around c. 7.5 Ma. Our findings suggest that the rapid rise of East Asian subtropical evergreen broadleaved forests occurred in the late Miocene, associated with the uplift of the Tibetan Plateau and the intensified East Asian monsoon, as well as the higher winter temperature and atmospheric CO2 levels. [ABSTRACT FROM AUTHOR]

[Display omitted] • A complete species-level phylogeny for Actaea was built based on five plastid and nuclear loci. • Actaea differentiated in East Asia and North America in the middle Eocene. • Actaea reached Europe twice in the late Miocene. • The sea-level changes played a key role in the exchanges of plants within East Asian margins. • The deciduous broad-leaved forests in the Northern Hemisphere began to rise in the middle Eocene. The deciduous broad-leaved forests (DBLFs) cover large temperate and subtropical high-altitude regions in the Northern Hemisphere. They are home to rich biodiversity, especially to numerous endemic and relict species. However, we know little about how this vegetation in the Northern Hemisphere has developed through time. Here, we used Actaea (Ranunculaceae), an herbaceous genus almost exclusively growing in the understory of the Northern Hemisphere DBLFs, to shed light on the historical assembly of this biome in the Northern Hemisphere. We present a complete species-level phylogenetic analysis of Actaea based on five plastid and nuclear loci. Using the phylogenetic framework, we estimated divergence times, ancestral ranges, and diversification rates. Phylogenetic analyses strongly support Actaea as monophyletic. Sections Podocarpae and Oligocarpae compose a clade, sister to all other Actaea. The sister relationship between sections Chloranthae and Souliea is strongly supported. Section Dichanthera is not monophyletic unless section Cimicifuga is included. Actaea originated in East Asia, likely the Qinghai-Tibet Plateau, in the late Paleocene (c. 57 Ma), and subsequently dispersed into North America in the middle Eocene (c. 43 Ma) via the Thulean bridge. Actaea reached Europe twice, Japan twice, and Taiwan once, and all these five colonization events occurred in the late Miocene-early Pliocene, a period when sea level dropped. Actaea began to diversify at c. 43 Ma. The section-level diversification took place at c. 27–37 Ma and the species-level diversification experienced accelerations twice, which occurred at c. 15 Ma and c. 5 Ma, respectively. Our findings suggest that the Northern Hemisphere DBLFs might have risen in the middle Eocene and further diversified in the late Eocene-Oligocene, middle Miocene and early Pliocene, in association with climatic deterioration during these four periods. [ABSTRACT FROM AUTHOR]

Coptis (Ranunculaceae) contains 15 species and is one of the pharmaceutically most important plant genera in eastern Asia. Understanding of the evolution of morphological characters and phylogenetic relationships within the genus is very limited. Here, we present the first comprehensive phylogenetic analysis of the genus based on two plastid and one nuclear markers. The phylogeny was reconstructed using Bayesian inference, as well as maximum parsimony and maximum likelihood methods. The Swofford-Olsen-Waddell-Hillis and Bayesian tests were used to assess the strength of the conflicts between traditional taxonomic units and those suggested by the phylogenetic inferences. Evolution of morphological characters was inferred using Bayesian method to identify synapomorphies for the infrageneric lineages. Our data recognize two strongly supported clades within Coptis. The first clade contains subgenus Coptis and section Japonocoptis of subgenus Metacoptis, supported by morphological characters, such as traits of the central leaflet base, petal color, and petal shape. The second clade consists of section Japonocoptis of subgenus Metacoptis. Coptis morii is not united with C. quinquefolia, in contrast with the view that C. morii is a synonym of C. quinquefolia. Two varieties of C. chinensis do not cluster together. Coptis groenlandica and C. lutescens are reduced to C. trifolia and C. japonica, respectively. Central leaflet base, sepal shape, and petal blade carry a strong phylogenetic signal in Coptis, while leaf type, sepal and petal color, and petal shape exhibit relatively higher levels of evolutionary flexibility. [ABSTRACT FROM AUTHOR]

This study investigates whether corporate governance affects the impact of the relationship between fundamental signals and stock returns using Taiwanese data. The study employs the endogenous switching model (ESM) of Hu and Schiantarelli (1998), which combines the response equation and governance index equation simultaneously. We divide the sample into strong and weak governance regimes. Our results suggest that stock returns respond differently in different governance regimes. The beneficial response is greater in the strong governance regime than in the weak one, suggesting that it is worth improving governance for firms. [ABSTRACT FROM AUTHOR]

• Phylogeny of Mahonia was built based on six nuclear and plastid loci. • Mahonia originated from western North America and dispersed to East Asia in the early Oligocene. • The diversification rate of Mahonia in East Asia is higher than that in western North America. • East Asian subtropical evergreen broadleaved forests rose in the early Miocene and further diversified in the late Miocene. The subtropical evergreen broadleaved forests (EBLFs) inhabit large areas of East Asia and harbor rich biodiversity and high endemism. However, the origin and evolution of biodiversity of East Asian subtropical EBLFs remain poorly understood. Here, we used Mahonia (Berberidaceae), an eastern Asian-western North American disjunct evergreen genus, to obtain new insights into the historical assembly of this biome. We present the most comprehensive phylogenetic analysis of Mahonia do date based on six nuclear and plastid loci. Using the phylogenetic framework, we estimated divergence times, reconstructed ancestral ranges, inferred evolutionary shift of habitats, and estimated diversification rates. Mahonia and each of its two groups (Orientales and Occidentales) are strongly supported as monophyletic. Mahonia originated in western North America during the late Eocene (c. 40.41 Ma) and subsequently dispersed into East Asia prior to the early Oligocene (c. 32.65 Ma). The North Atlantic Land Bridge might have played an important role in population exchanges of Mahonia between East Asia and western North America. The western North American Occidentales began to diversify in summer-dry climates and open landscapes in the early Miocene, whereas the eastern Asian Orientales began to diversify in subtropical EBLFs in the early Miocene and furthermore had a rapid lineage accumulation since the late Miocene. The net diversification rate of Mahonia in eastern Asia appeared to be higher than that in western North America, which is ascribed to lower extinction rates and ecological opportunity. Our findings suggest that western North America is a source of biodiversity of East Asian subtropical EBLFs. This biome in eastern Asia began to rise in the early Miocene and further diversified in the late Miocene, driven by the intensifying East Asian summer monsoon during these two periods. [ABSTRACT FROM AUTHOR]