Alon Philosof is interested in the ecological role of viruses (mainly phages) in the marine environment. Globally, viruses constitute a large and abundant biomass, and are the second largest biomass in the oceans, exceeded only by the total biomass of bacteria. He is  especially interested in understanding the temporal and spatial dynamics of host-phage interactions in the environment and the role of viruses as drivers of microbial growth, metabolism and mortality and their ultimate effect on biogeochemical cycles. Philosof earned his PhD from the Israel Institute of Technology (Technion) where he worked with Prof. Oded Beja on viruses found in marine surface waters. Using Metagenomics and Metatranscriptomics, Philosof has been able to find new groups of viruses, new viral metabolic functions and to characterize their daily activity. Currently a postdoc with Victoria Orphan at Caltech, his research aims to develop and use direct in situ measurements of viral production, viral activity and transfer of nutrients that will supplement meta-omic methods and will broaden our understanding of the role of viruses in global biogeochemical cycles.