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The discontinuous geographic distribution pattern of plants in the north temperate zone has been a focus of biogeographic research, especially concerning the mechanisms behind the formation of such a pattern and the spatial and temporal evolution of this intermittent distribution pattern. Hypotheses of boreotropical origin, land bridge migration, and out‐of‐Tibet have been proposed to explain the formation of the discontinuous distribution pattern. The distribution of Lonicera shows a typical Europe–Asia–North America discontinuous distribution, which makes for a good case study to investigate the above three hypotheses. In this study, we inferred the phylogeny based on plastid genomes and a nuclear data set with broad taxon sampling, covering 83 species representing two subgenera and four sections. Both nuclear and plastid phylogenetic analyses found section Isika polyphyletic, while sections Nintooa, Isoxylosteum, and Coelxylosteum were monophyletic in subgenus Chamaecerasus. Based on the nuclear and chloroplast phylogeny, we suggest transferring Lonicera maximowiczii and Lonicera tangutica into section Nintooa. Reconstruction of ancestral areas suggests that Lonicera originated in the Qinghai–Tibetan Plateau (QTP) and/or Asia, and subsequently dispersed to other regions. The aridification of the Asian interior may have facilitated the rapid radiation of Lonicera in the region. At the same time, the uplifts of the Tibetan Plateau appear to have triggered the spread and recent rapid diversification of the genus on the QTP and adjacent areas. Overall, our results deepen the understanding of the evolutionary diversification history of Lonicera. [ABSTRACT FROM AUTHOR]

n‐Alkanes are widely used in paleoenvironmental reconstructions. However, our understanding of changes in the distribution of n‐alkanes with climatic and environmental factors remains unclear in arid/semi‐arid regions. We sampled 26 surface sediments from three climatic zones across the southwestern Tibetan Plateau to evaluate the sensitivity of chain length distributions of n‐alkanes to climatic and environmental parameters. Our observations demonstrate that average chain length (ACL), proportion of aquatic macrophyte (Paq), carbon preference index (CPI) and ratio of the contents of nC27 and nC31 (nC27/nC31) are all sensitive to hydroclimatic conditions. In contrast to commonly‐adopted assumptions, the correlations between these indices and hydrological parameters are not always good, which indicates that the interpretation of n‐alkane indices is special on the southwestern Tibetan Plateau. These might be related to the vegetation characteristics and seasonality of biological activity, and need to be considered in paleoclimatic reconstruction. The impact of seasonal precipitation on n‐alkanes indices was also evaluated. [ABSTRACT FROM AUTHOR]