Between the Upper Jurassic and Lower Cretaceous, a unique terrestrial and freshwater habitat began to emerge in Southeast Asia. Its great biodiversity is exceptionally well preserved in lake sediments in Western Liaoning in North China. The fossil assemblage of the Jehol Biota was first defined by William Grabau in 1923 based on the representative fossil finds of the freshwater Teleost fish Lycoptera and the chonchostracan Eosetheria. The majority of the Mesozoic fossils on our display come from this world renowned fossil assemblage that has provided crucial evidence for some important discoveries in evolutionary history such as the direct ancestors of birds, and the origins of feathers.