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Abstract: Aim: The Sino‐Himalayas have higher species richness than adjacent regions, making them a global biodiversity hotspot. Various mechanisms, including ecological constraints, energetic constraints, diversification rate (DivRate) variation, time‐for‐speciation effect and multiple colonizations, have been posited to explain this pattern. We used pheasants (Aves: Phasianidae) as a model group to test these hypotheses and to understand the ecological and evolutionary processes that have generated the extraordinary diversity in these mountains. Location: Sino‐Himalayas and adjacent regions. Taxon: Pheasants. Methods: Using distribution maps predicted by species distribution models (SDMs) and a time‐calibrated phylogeny for pheasants, we examined the relationships between species richness and predictors including net primary productivity (NPP), niche diversity (NicheDiv), DivRate, evolutionary time (EvolTime) and colonization frequency using Pearson's correlations and structural equation modelling (SEM). We reconstructed ancestral ranges at nodes and examined basal/derived species patterns to reveal the mechanisms underlying species richness gradients in the Sino‐Himalayas. Results: We found that ancestral pheasants originated in Africa in the early Oligocene (~33 Ma), and then colonized the Sino‐Himalayan mountains and other regions. In the Sino‐Himalayas, species richness was strongly related to DivRate, NPP, NicheDiv and colonization frequency, but weakly correlated with EvolTime. The direct effects of NicheDiv and DivRate on richness were stronger than NPP and EvolTime. NPP indirectly influenced species richness via DivRate, but its effect on richness via NicheDiv was relatively weak. Main conclusions: Higher species diversity in the Sino‐Himalayas was generated by both ecological and evolutionary mechanisms. An increase in available niches, rapid diversifications and multiple colonizations was found to be key direct processes for the build‐up of the diversity hotspots of pheasants in the Sino‐Himalayan mountains. Productivity had an important but indirect effect on species richness, which worked through increased DivRate. Our study offers new insights on species accumulation in the Sino‐Himalayas and provides a useful model for understanding other biodiversity hotspots. [ABSTRACT FROM AUTHOR]

Aim To infer the biogeographical history of the avian clade Paridae (tits and chickadees) using methods based on discrete, a priori defined, geographical areas and a method that uses actual species distributions and a relaxed random walk in a Bayesian context. We compared their relative performances and how different area codings influenced the outcome in the discrete analyses. Location Holarctic, Indomalaya, Afrotropics. Methods The phylogeny was reconstructed using Bayesian inference and time-calibrated using published substitution rates and a fossil calibration point. The discrete analyses were performed in BioGeo BEARS. For the probabilistic diffusion analysis, the extant distribution of each species was shaped as polygons in Google Earth and analysed together with the posterior distribution of time-calibrated trees in beast. The diffusion process was modelled as a relaxed random walk. Results The earliest divergences occurred between 10 and 15 Ma and the probabilistic diffusion analysis, and one of the discrete analyses indicated that the parids originated in the mountains of East Asia (Sino-Himalayas). Due to a different categorization of the geographical areas, a partly overlapping but conceptually different region was indicated in the second discrete analysis. Between 8 and 5 Ma parids started to spread from the Sino-Himalayas and became established in North America and Africa before 5 Ma. However, the inferred dispersal patterns differed between the analyses. Main conclusion Overall, the analyses were congruent and together with the divergence time analysis provided a solid biogeographical history for the parids. However, some discrepancies were evident and the diffusion analysis often indicated a more stationary pattern in the Sino-Himalayas in contrast to the more widespread ancestors indicated by the discrete analyses. The discrete analyses were influenced both by the biogeographical model and delimitation of the a priori areas. [ABSTRACT FROM AUTHOR]

As one of the most prominent topographical features on Earth, the Qinghai-Tibetan plateau (QTP) underwent a long and complex history of the QTP uplift from the collision of the Indian and the Eurasian plates to the present. At its southern and southeastern margins, it is flanked by the most significant hotspots of organismic diversity of the northern hemisphere (including birds), the Sino-Himalayan mountain forests. In contrast, the central plateau region itself harbours species-poor communities but also a good number of endemics that presumably evolved from rather ancient (pre-Pleistocene) phylogenetic lineage splits. We discuss the evolutionary history of QTP passerines from a twofold perspective including examples from our own research. First, we provide an overview of those alpine QTP endemics that represent late Miocene and Pliocene lineage splits, i.e. early colonisations to the central alpine QTP region. As an example, true rosefinches (genus Carpodacus) presumably evolved from a forested eastern QTP centre of origin and colonised the (semi-)open plateau habitats several times independently. Second, we discuss younger speciation events corresponding to phylogeographic east-west divides along the southern QTP margin. A multidisciplinary approach combining genetic, bioacoustic and morphological markers shed new light on the phylogenetic relationships of Pnoepyga wren babblers and on the intraspecific subdivision of the Buff-barred Warbler ( Phylloscopus pulcher). [ABSTRACT FROM AUTHOR]