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Abstract Background Geological events and climatic changes played important roles in shaping population differentiation and distribution within species. In China, populations in many species have contracted and expanded responding to environmental changes with the uplift of the Qinghai-Tibet Plateau (QTP) and glacial cycles during Pleistocene. In this study, we analysed the population structure of Godlewski’s Bunting, Emberiza godlewskii, to determine the effects of major historical events, geographic barriers and past climatic changes on phylogenetic divergence and historical demographic dynamics of this species. Results A phylogeny based on concatenated mitochondrial and nuclear DNA datasets show two (northern and southern) clades approximately diverged 3.26 million years ago (Ma). The West Qinling Mountains serve as a dividing line between the two lineages. Both lineages experienced a recent demographic expansion during interglacial periods (marine isotope stages (MISs) 2–6). Bayesian skyline plots and the results of ecological niche modelling suggested a more intensive expansion of the northern lineage during the late Pleistocene, whereas the southern lineage was comparatively mild in population growth. Conclusions Our results provide insights into the distribution patterns of avian taxa and the possible mechanisms for a south and north divergence model in China. The deep divergence may have been shaped by the uplift of the QTP. Habitat preferences might have facilitated the lineage divergence for E. godlewskii. Moreover, the West Qinling Mountains act as a dividing line between the two lineages, indicating a novel phylogeographic pattern of organisms in China. The difference in population expansion mode between two lineages resulted from different effects caused by the climate of the LGM and the subsequent habitat changes accompanying the arrival of a colder climate in northern and southern regions of China.

Abstract Background Non-human primates have long been identified to harbour different species of Plasmodium. Long-tailed macaques (Macaca fascicularis), in particular, are reservoirs for P. knowlesi, P. inui, P. cynomolgi, P. coatneyi and P. fieldi. A previous study conducted in Sarawak, Malaysian Borneo, however revealed that long-tailed macaques could potentially harbour novel species of Plasmodium based on sequences of small subunit ribosomal RNA and circumsporozoite genes. To further validate this finding, the mitochondrial genome and the apicoplast caseinolytic protease M genes of Plasmodium spp. were sequenced from 43 long-tailed macaque blood samples. Results Apart from several named species of malaria parasites, long-tailed macaques were found to be potentially infected with novel species of Plasmodium, namely one we refer to as “P. inui-like.” This group of parasites bifurcated into two monophyletic clades indicating the presence of two distinct sub-populations. Further analyses, which relied on the assumption of strict co-phylogeny between hosts and parasites, estimated a population expansion event of between 150,000 to 250,000 years before present of one of these sub-populations that preceded that of the expansion of P. knowlesi. Furthermore, both sub-populations were found to have diverged from a common ancestor of P. inui approximately 1.5 million years ago. In addition, the phylogenetic analyses also demonstrated that long-tailed macaques are new hosts for P. simiovale. Conclusions Malaria infections of long-tailed macaques of Sarawak, Malaysian Borneo are complex and include a novel species of Plasmodium that is phylogenetically distinct from P. inui. These macaques are new natural hosts of P. simiovale, a species previously described only in toque monkeys (Macaca sinica) in Sri Lanka. The results suggest that ecological factors could affect the evolution of malaria parasites.

Background: Non-human primates have long been identified to harbour different species of Plasmodium. Long-tailed macaques (Macaca fascicularis), in particular, are reservoirs for P. knowlesi, P. inui, P. cynomolgi, P. coatneyi and P. fieldi. A previous study conducted in Sarawak, Malaysian Borneo, however revealed that long-tailed macaques could potentially harbour novel species of Plasmodium based on sequences of small subunit ribosomal RNA and circumsporozoite genes. To further validate this finding, the mitochondrial genome and the apicoplast caseinolytic protease M genes of Plasmodium spp. were sequenced from 43 long-tailed macaque blood samples. Results: Apart from several named species of malaria parasites, long-tailed macaques were found to be potentially infected with novel species of Plasmodium, namely one we refer to as “P. inui-like.” This group of parasites bifurcated into two monophyletic clades indicating the presence of two distinct sub-populations. Further analyses, which relied on the assumption of strict co-phylogeny between hosts and parasites, estimated a population expansion event of between 150,000 to 250,000 years before present of one of these sub-populations that preceded that of the expansion of P. knowlesi. Furthermore, both sub-populations were found to have diverged from a common ancestor of P. inui approximately 1.5 million years ago. In addition, the phylogenetic analyses also demonstrated that long-tailed macaques are new hosts for P. simiovale. Conclusions: Malaria infections of long-tailed macaques of Sarawak, Malaysian Borneo are complex and include a novel species of Plasmodium that is phylogenetically distinct from P. inui. These macaques are new natural hosts of P. simiovale, a species previously described only in toque monkeys (Macaca sinica) in Sri Lanka. The results suggest that ecological factors could affect the evolution of malaria parasites. [ABSTRACT FROM AUTHOR]