My research is at the interface of molecular and organismal biology.  I am interested in the application of comparative genomics to investigate key problems in organismal evolution, and the combination of genomic and paleontological information to study evolution.  I am interested in the early Earth, the coevolution of life and Earth, the origin and early diversification of cellular life and eukaryogenesis.  I am interested in major evolutionary transitions and I have recently been working at developing a timescale for life on Earth, the origin of animals and the phylogeny of non-bilaterian animals (sponges, jellifishes, comb jellies, corals and the elusive placozoans).  I am interested in the evolution of the Ecdysozoa (the moulting animals), particularly the tardigrades (water bears), onychophora (velvet worms) and Arthropoda (insects, millipedes, crustaceans, spiders etc).  I use Ecdysozoa as a model to study patterns and processes of colonisation of land. I am intereststed in the evolution of sensory functions (particularly chemoreception and life reception), as detecting these envirounmental cues is key for a diversity of life forms (both unicellular and multicellular). Finally, I am interested in the study and development of phylogenetic-based methods of analyses, and I have been developing and implementing in software supertree reconstruction methods. I have an interest in Astrobiology and I have been collaborating with the NASA Astrobiology institute from 2002 to 2018.