Joshua Weitz, Associate Professor
Ph.D., Physics, Massachusetts Institute of Technology, 2003
Office: Cherry Emerson 219
Theoretical ecology; evolutionary ecology of microbial & viral communities; biological networks; vascular plants; scaling laws; disease dynamics; interacting particle systems.
Evolutionary ecology of bacterial viruses
Bacterial viruses (bacteriophage) are the most abundant organisms on Earth. Typical densities of phage are approximately 10 billion per liter of seawater and even higher in soil samples. Despite their ubiquitous presence, we have only a limited understanding of the evolutionary ecology of bacteria and bacteriophage. I plan to begin a multidisciplinary research program on phage that includes the study of (i) the generation and maintenance of microbial and viral diversity; (ii) the evolution of life-history switches in phage; (iii) basic mechanisms of host-phage population dynamics; and (iv) the role of phage in altering infectious disease.
Scaling and biological networks
Networks are a central element in biological functioning that span gene regulation to resource delivery to ecosystem organization. Projects in the group include the use of empirical analysis with scaling theory to assess internal architecture of resource delivery networks from the xylem networks of vascular plants to the cardiovascular networks of mammals. In addition, I am interested in networks at the ecosystem scale, whether the emergence of size-structured food webs or the dynamics of riparian vegetation within river networks. Future work will include studies of competition and evolution of biological networks from a game-theoretic perspective.
Analysis of biological systems depends on scale. I am interested in the foundations of two important approaches to study multi-scale phenomena in biological systems: (i) adaptive dynamics; and (ii) metabolic theory. I emphasize application of both theories to novel systems as well as the development of new methodologies, for example the extension of metabolic theory to predator-prey dynamics.
Jiang, X, Weitz JS, Dushoff J. In Press. A non-negative matrix factorization framework for identifying modular patterns in metagenomic profile data. Journal of Mathematical Biology.
Price, CA, Wing S, Weitz JS. In Press. Scaling and structure of dicotyledonous leaf venation networks. Ecology Letters.
Price, CA, Weitz JS. In Press. Allometric covariation: a hallmark behavior of plants and leaves. New Phytologist.
Joh, RI, Weitz JS. 2011. To lyse or not to lyse: transient-mediated stochastic fate determination in cells infected by bacteriophages. PLoS Computational Biology. 7:e1002006.
Kislyuk, AO, Haegeman B, Bergman NH, Weitz JS. 2011. Genomic fluidity: an integrative view of gene diversity within microbial populations. BMC Genomics. 12:32.
Serra, M, Smith HA, Weitz JS, Snell TW. 2011. Analysing threshold effects in the sexual dynamics of cyclically parthenogenetic rotifer populations . Hydrobiologia. 662:121-130.
Price, CA, Symonova O, Mileyko Y, Hilley T, Weitz JS. 2011. LEAF GUI: segmenting and analyzing the structure of leaf veins and areoles. Plant Physiology. 155:236-245.
Flores, CO, Meyer JR, Valverde S, Farr L, Weitz JS. 2011. Statistical structure of host-phage interactions . Proceedings of the National Academy of Sciences. 108:E288-E297.
Menge, D NL, Ballantyne F, Weitz JS. 2011. Dynamics of nutrient uptake strategies: Lessons from the tortoise and the hare. Theoretical Ecology. 4:163-177.
Mitchell, GJ, Nelson DC, Weitz JS. 2010. Quantifying enzymatic lysis: estimating the combined effects of chemistry, physiology, and physics. Physical Biology. 7:046002.