Recently, Professor Wu Shaoyuan, director of Jiangsu Key Laboratory of Phylogenomics and Comparative Genomics led his team and achieved important progress in the research field of the evolution of mammals. Related result was published in top international academic journal PNAS by the title of “Genomicevidence reveals a radiation of placental mammals uninterrupted by the KPgboundary” on August 14, 2017. As the first author and correspondent author, JSNU published this result online in PNAS Plus.
“The timing of the diversification of placental mammals relative to the Cretaceous–Paleogene (KPg) boundary mass extinction remains highly controversial. In particular, there have been seemingly irreconcilable differences in the dating of the early placental radiation not only between fossil-based and molecular datasets but also among molecular datasets. To help resolve this discrepancy, we performed genome-scale analyses using 4,388 loci from 90 taxa, including representatives of all extant placental orders and transcriptome data from flying lemurs (Dermoptera) and pangolins (Pholidota). Depending on the gene partitioning scheme, molecular clock model, and genic deviation from molecular clock assumptions, extensive sensitivity analyses recovered widely varying diversification scenarios for placental mammals from a given gene set, ranging from a deep Cretaceous origin and diversification to a scenario spanning the KPg boundary, suggesting that the use of suboptimal molecular clock markers and methodologies is a major cause of controversies regarding placental diversification timing. We demonstrate that reconciliation between molecular and paleontological estimates of placental divergence times can be achieved using the appropriate clock model and gene partitioning scheme while accounting for the degree to which individual genes violate molecular clock assumptions. A birth-death-shift analysis suggests that placental mammals underwent a continuous radiation across the KPg boundary without apparent interruption by the mass extinction, paralleling a genus-level radiation of multituberculates and ecomorphological diversification of both multituberculates and therians. These findings suggest that the KPg catastrophe evidently played a limited role in placental diversification, which, instead, was likely a delayed response to the slightly earlier radiation of angiosperms.”
Professor Wu Shaoyuan achieved his doctor degree at Harvard University. He is the director of Jiangsu Key Laboratory of Phylogenomics and Comparative Genomics and the academic leader of Excellent Science and Technology Innovative Team of Jiangsu Province. He research interest is Biological Information and Comparative Genomics, including Phylogenetic Analysis and Evolutionary Modeling of applying massive Genomic data and the Evolutionary Biology of tumor. In recent five years, he has published 11 papers in top international academic journals like PNAS, Evolution and Nature. Totally, his papers have been cited for 504times. Among those papers, the highest citation of one paper reaches 235 times (GoogleScholar, Aug. 2017). He is also the referee of Molecular Biology and Evolution, Bioinformatics, Journal of Heredity, Scientific Reports, PLoS One and other international academic journals.
This research is funded by National Natural Foundation of China and Predominant Discipline of Jiangsu Province.
