Evolutionary radiation of the Jehol Biota: chronological and ecological perspectives

The Jehol Biota, preserved in the lacustrine sediments of Liaoning Province, northeast China, has provided a new window for understanding Early Cretaceous terrestrial ecosystems. Based on recent geochronological and biostratigraphic studies of the fossil-bearing deposits, a preliminary temporal framework has been established and suggests that the Jehol Biota had lasted for at least I I Ma during the late Early Cretaceous (131-120 Ma). The development of the Jehol Biota can be divided into three major phases, with the most significant biological radiations occurring in the second phase between the Barremian and Aptian (approximately 125 Ma). Thanks to a diverse forest environment, major vertebrate groups, i.e. pterosaurs, dinosaurs, birds and mammals, in the Jehol Biota are characterized by a remarkably high percentage of arboreal and herbivorous forms. In addition to strong phylogenetic and morphological differentiation and high taxonomic diversity, the Jehol Biota is also characterized by significant dietary differentiation and biological interactions, i.e. competition and co-evolution between various animal groups, in an environment shaped by tectonic activities and palaeoclimatic changes both at a global and local scale. Copyright (c) 2006 John Wiley & Sons, Ltd.