The abrupt climate change at the Eocene-Oligocene boundary and the emergence of South-East Asia triggered the spread of sapindaceous lineages.

Background and Aims Paleoclimatic data indicate that an abrupt climate change occurred at the Eocene-Oligocene (E-O) boundary affecting the distribution of tropical forests on Earth. The same period has seen the emergence of South-East (SE) Asia, caused by the collision of the Eurasian and Australian plates. How the combination of these climatic and geomorphological factors affected the spatio-temporal history of angiosperms is little known. This topic is investigated by using the worldwide sapindaceous clade as a case study. Methods Analyses of divergence time inference, diversification and biogeography (constrained by paleogeography) are applied to a combined plastid and nuclear DNA sequence data set. Biogeographical and diversification analyses are performed over a set of trees to take phylogenetic and dating uncertainty into account. Results are analysed in the context of past climatic fluctuations. Key Results An increase in the number of dispersal events at the E-O boundary is recorded, which intensified during the Miocene. This pattern is associated with a higher rate in the emergence of new genera. These results are discussed in light of the geomorphological importance of SE Asia, which acted as a tropical bridge allowing multiple contacts between areas and additional speciation across landmasses derived from Laurasia and Gondwana. Conclusions This study demonstrates the importance of the combined effect of geomorphological (the emergence of most islands in SE Asia approx. 30 million years ago) and climatic (the dramatic E-O climate change that shifted the tropical belt and reduced sea levels) factors in shaping species distribution within the sapindaceous clade.

Proto-South-East Asia as a trigger of early angiosperm diversification

Darwin described as an 'abominable mystery' the abrupt origin of angiosperms in the mid-Cretaceous and the high diversification rates in their early history. The father of evolutionary theory could not fathom this rapid diversification and rather invoked that 'there was during long ages a small isolated continent in the S. hemisphere, which served as the birthplace of the higher plants'. In this essay, we comment on the spatial origin of angiosperms, but focus primarily on understanding the abiotic factors that promoted the early diversification of angiosperms by reviewing palaeobotanical, palaeogeographical, phylogenetics and biogeographical evidence. We argue that islands located in the region today occupied by South-East Asia played a major role in angiosperm diversification during the Late Jurassic and Early Cretaceous.

Childhood cancer mortality in America, Asia, and Oceania, 1970 through 2007.

BACKGROUND: Over the last 4 decades, childhood cancer mortality declined in most developed areas of the world. However, scant information is available from middle-income and developing countries. The authors analyzed and compared patterns in childhood cancer mortality in 24 developed and middle-income countries in America, Asia, and Oceania between 1970 and 2007. METHODS: Childhood age-standardized annual mortality rates were derived from the World Health Organization (WHO) database for all neoplasms, bone and kidney cancer, non-Hodgkin lymphoma (NHL), and leukemias. RESULTS: Since 1970, rates for all childhood cancers dropped from approximately 8 per 100,000 boys to 3 per 100,000 boys and from 6 per 100,000 girls to 2 per 100,000 girls in North America and Japan. Latin American countries registered rates of approximately 5 per 100,000 boys and 4 per 100,000 girls for 2005 through 2007, similar to the rates registered in more developed areas in the early 1980s. Similar patterns were observed for leukemias, for which the mortality rates were 0.81 per 100,000 boys and 0.55 per 100,000 girls in North America, 0.86 per 100,000 boys and 0.68 per 100,000 girls in Japan, and 1.98 per 100,000 boys and 1.65 per 100,000 girls in Latin America for 2005 through 2007. Bone cancer rates for 2005 through 2007 were approximately 2-fold higher in Argentina than in the United States. During the same period, Mexico registered the highest rate for kidney cancer and Colombia registered the highest rate for NHL, whereas the lowest rates were registered by Japan for kidney and by Japan and the United States for NHL. CONCLUSIONS: Improvements in the adoption of current integrated treatment protocols in Latin American and other lower- and middle-income countries worldwide would avoid a substantial proportion of childhood cancer deaths.

Note on seismic hazard assessment using gradient of uplift velocities on the Turan Block (Central Asia)

Uplift gradients can provide the location of highly strained zones, which can be considered to be seismic. The Turan block (Central Asia) contains zones with high gradient of uplift velocities, above the threshold 0.04mm km-1year-1. Some of these zones are associated with important seismic activity and others are not correlated with any recent important recorded earthquakes, however, recent faults scarps as well as diverted rivers may indicate a recent tectonic activity. This threshold of gradient is probably a significant rheologic property of the upper crust. On the basis of these considerations the Uzboy river area is proposed as a potential high seismic hazard zone.

Genetic structure of the Lesser Gymnure (Genus Hylomys) in SE-Asia: evidence for two species

The Lesser Gymnure is a small galericine Insectivore living in the mainland forests of Southeast Asia, including the major islands of Sumatra, Java and Borneo. It is the only representative of the supposed monospecific genus Hylomys which is morphologically rather constant over its geographic range. Only marginal subspecific differentiation is currently recognized based in slight pelage colour variations. We report here the results of 35 gene loci revealed by protein electrophoresis on 23 specimens sampled over most of Southeast Asia. They were compared with outgroup, Erinaceaus europeaus, member of a distinct subfamily. The surveyed populations of Lesser Gymnures clearly group themselves into distinct taxa, one of which seems restricted to Sumatra, while the other occupies the whole geographic range. The genetic distance between these groups is two times greater than the divergence observed within groups: it is of the same order of magnitude as what is usually reported for congeneric mammal species, which supports their specific distinction. The lack of gene flow is also demonstrated by several diagnostic loci defining unambiguously each species. Both are only distantly related to the outgroup, a result which is consistant with their actual classification into two distinct subfamilies (Erinaceae and Galericinae). Concordant genetic and geographic subdivision of the widespread species further suggest that eustatic sea level changes during the Pleistocene produced predictable patterns in species differentiation.

Is chytridiomycosis an emerging infectious disease in Asia?

The disease chytridiomycosis, caused by the fungus Batrachochytrium dendrobatidis (Bd), has caused dramatic amphibian population declines and extinctions in Australia, Central and North America, and Europe. Bd is associated with >200 species extinctions of amphibians, but not all species that become infected are susceptible to the disease. Specifically, Bd has rapidly emerged in some areas of the world, such as in Australia, USA, and throughout Central and South America, causing population and species collapse. The mechanism behind the rapid global emergence of the disease is poorly understood, in part due to an incomplete picture of the global distribution of Bd. At present, there is a considerable amount of geographic bias in survey effort for Bd, with Asia being the most neglected continent. To date, Bd surveys have been published for few Asian countries, and infected amphibians have been reported only from Indonesia, South Korea, China and Japan. Thus far, there have been no substantiated reports of enigmatic or suspected disease-caused population declines of the kind that has been attributed to Bd in other areas. In order to gain a more detailed picture of the distribution of Bd in Asia, we undertook a widespread, opportunistic survey of over 3,000 amphibians for Bd throughout Asia and adjoining Papua New Guinea. Survey sites spanned 15 countries, approximately 36° latitude, 111° longitude, and over 2000 m in elevation. Bd prevalence was very low throughout our survey area (2.35% overall) and infected animals were not clumped as would be expected in epizootic events. This suggests that Bd is either newly emerging in Asia, endemic at low prevalence, or that some other ecological factor is preventing Bd from fully invading Asian amphibians. The current observed pattern in Asia differs from that in many other parts of the world.

Origin and genome evolution of polyploid green toads in Central Asia: evidence from microsatellite markers.

Polyploidization, which is expected to trigger major genomic reorganizations, occurs much less commonly in animals than in plants, possibly because of constraints imposed by sex-determination systems. We investigated the origins and consequences of allopolyploidization in Palearctic green toads (Bufo viridis subgroup) from Central Asia, with three ploidy levels and different modes of genome transmission (sexual versus clonal), to (i) establish a topology for the reticulate phylogeny in a species-rich radiation involving several closely related lineages and (ii) explore processes of genomic reorganization that may follow polyploidization. Sibship analyses based on 30 cross-amplifying microsatellite markers substantiated the maternal origins and revealed the paternal origins and relationships of subgenomes in allopolyploids. Analyses of the synteny of linkage groups identified three markers affected by translocation events, which occurred only within the paternally inherited subgenomes of allopolyploid toads and exclusively affected the linkage group that determines sex in several diploid species of the green toad radiation. Recombination rates did not differ between diploid and polyploid toad species, and were overall much reduced in males, independent of linkage group and ploidy levels. Clonally transmitted subgenomes in allotriploid toads provided support for strong genetic drift, presumably resulting from recombination arrest. The Palearctic green toad radiation seems to offer unique opportunities to investigate the consequences of polyploidization and clonal transmission on the dynamics of genomes in vertebrates.