His research focuses on the deep past such as the World Heritage fossil deposits at Riversleigh, the fragile present such as conservation through sustainable use of native resources including having native animals as pets, securing the future based on the wisdom of the fossil record, and trying to bring extinct species (e.g., the Gastric-brooding Frog and the Thylacine) back into the world of the living. He has supervised/co-supervised more than 80 research student degrees, produced over 350 scientific publications including 15 books and received a range of awards including Fellowships in the Australian Academy of Science, Royal Society of NSW, Royal Zoological Society of New South Wales, Australian College of Educators, Eureka Prize for Promotion of Science and Member of the Order of Australia.