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Aim: The timing of reproduction is a major determinant of the geographical distribution of plant species and resulting patterns of community assembly, yet few studies have assessed how the reproductive phenology of plant assemblages varies across large geographical and environmental gradients. In addition, it remains poorly known to what extent phenological trends and their drivers differ between flowering and fruiting phases or among different growth forms. To address these knowledge gaps, we examined the reproductive phenology and potential climatic drivers in herbaceous and woody species in ecosystems across China that varied in climate (temperate to tropical) seasonality and elevation. Location: China. Methods: We used data from the Flora Republicae Popularis Sinicae to estimate angiosperm flowering (n = 16,717 species) and fruiting (n = 11,605) phenology for 100 x 100 km grid cells (n = 943) throughout China. We assessed large‐scale geographical trends in mean flowering and fruiting date and the time needed for fruit development. The relationships of these phenological variables with seven climate variables were examined using both ordinary and spatial linear regression. Results: Higher latitudes and elevations had considerably reduced length of the reproductive season, with later flowering and earlier fruiting than lower latitudes and elevations. Woody plant assemblages flowered markedly earlier and needed three times longer for fruit development, and tended to show steeper geographical trends in reproductive phenology than herbaceous assemblages. Herbs and woody species differed strongly in their climatic triggers of flowering but largely shared the same cues for fruiting. Main conclusions: Woody species compensate for longer seed development times by an earlier onset of flowering, yet reproduction in both life‐forms has stronger climatic constraints. Distinct climatic drivers suggest that herbaceous and woody species assemblages will respond differently to climate change. Overall, our findings underpin the role of reproductive phenology as a key biological mechanism through which climate shapes large‐scale geographical trends in species richness, phylogenetic diversity and community assembly. [ABSTRACT FROM AUTHOR]

Aim: We examine how environmental variability at seasonal and interannual time‐scales influences evolutionary trajectories and the role of plasticity in response to recent and future climate change at biogeographic scales. We investigate the interplay of selection pressures at chronic (performance) and acute (thermal stress) time‐scales. Location: Colorado, USA. Time period: 1950–2099. Major taxa studied: A montane butterfly, clouded sulphur (Colias eriphyle W.H. Edwards, 1876). Methods: We leverage field and laboratory data to construct phenotype‐based models that predict fitness and evolutionary responses to recent and future climate change. Our focal phenotype, wing solar absorptivity, responds plastically to developmental (pupal) temperatures and determines adult fitness via its influence on body temperature. Results: We project that phenology accelerates with decreasing elevation and climate change, but gradients in pupal and adult temperature with climate change are modest. Fitness of the first generation is predicted to decrease at low elevations and increase at high elevations with warming. Elevational clines in optimal wing absorptivity shift towards lower absorptivities with warming. We project that temporal shifts from selection for wing darkening (to extend flight time) to selection for wing lightening (to avoid overheating) in some cool, montane locations will ultimately impose fitness costs. Main conclusions: Our analysis suggests that shifts in the balance of selection between acute and chronic responses to environmental variation will alter biogeographic responses to climate change. Evolutionary lags may ultimately confer greater sensitivity to climate change, but plasticity can reduce evolutionary lags by facilitating trait evolution. [ABSTRACT FROM AUTHOR]

Aim: A geophylogeny, generated by mapping a phylogeny onto geographic regions, graphically summarizes large‐scale genetic variation over space and time, and is consequently crucial for conceptual understanding and visualization of global biogeographic patterns. The rapidly expanding DNA barcoding data with geographic coordinates associated with each specimen have dramatically increased the number of global phylogeographic studies that would benefit from software generating geophylogenies. A number of software programs have been developed, some with advanced features, but they either require additional software or are lacking in quality, especially in geographic resolution. Innovation: PGT (PhylogeographicTree), freely available at http://dambe.bio.uottawa.ca/PGT/PGT.aspx, combines the highest map quality and user‐friendliness. It accesses Microsoft Bing Maps and Google Maps seamlessly and generates geophylogenies on high‐resolution regular or terrain maps. Only a few mouse clicks are needed from PGT installation to the generation of high‐resolution geophylogenies, making PGT perfect for both teaching and research in global ecology and biogeography. The input tree can be in NEXUS or Newick format, and the geographic data with latitude and longitude values can be in tab‐delimited or comma‐delimited format such as those exported from spreadsheet programs. A Quick‐Start guide is included in the built‐in help system. Main conclusions: PGT is simpler, more elegant, and of much higher quality than alternatives for plotting phylogenetic trees over geographic regions for visualizing distribution of biodiversity over space and time. [ABSTRACT FROM AUTHOR]

Aim Hotspots of biodiversity are often associated with areas that have undergone orogenic activity during recent geological history. Mountain uplifts are known to catalyse species radiation but their impact on evolutionarily stable taxa such as many trees remains little understood. The oak Quercus aquifolioides is endemic to yet widely distributed across the Hengduanshan Biodiversity Hotspot in the Eastern Himalayas. Here, we investigate how the region's Neogene and Quaternary history has driven the species' past population dynamics and the resulting extant patterns of intraspecific diversity. Location Hengduanshan Biodiversity Hotspot in SW China. Methods We sampled 58 populations throughout the species range and genotyped a total of 959 individuals at four chloroplast DNA fragments and 11 nuclear microsatellite loci. Phylogenetic reconstructions, molecular dating techniques and ancestral area reconstructions were used in combination with population genetic statistics to infer the biogeographical history of Q. aquifolioides. The phylogeographical study was complemented by a survey of fossil records and a niche modelling exercise. Results Combined molecular and fossil evidence indicates that Q. aquifolioides descended during the late Miocene from the central Qinghai-Tibet Plateau into Tibet and the western Sichuan Plateau, and from there, into the area of highest endemism in the Hengduan Mountains sensu lato. Great apparent population stability and a haplotype 'radiation' in this area contrasted with marked extinction-recolonization dynamics and reduced population diversity in Tibet. We found evidence for extremely limited seed gene flow but extensive pollen gene flow (global FST: cp DNA = 0.98, nSSR = 0.07) with signals of asymmetric pollen dispersal from the Hengduan Mountains into Tibet. Main conclusion Our results provide insights of unprecedented detail into the ancient biogeographical history of the Hengduanshan Biodiversity Hotspot, suggesting that past environmental changes in the region may have catalysed radiative diversifications within species much in the same way as among species. [ABSTRACT FROM AUTHOR]

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