Animal development converts a sphere or disk of cells into a multilayered structure capable of directed growth and complex physiological function. Tissue movements during morphogenesis are coordinated between multiple layers of loose mesenchymal and compact laminar epithelial sheets, each undergoing independent rearrangements. Extracellular matrices at the interfaces can serve as either glue or lubricants to channel 2D movements into 3D shapes. My talk will survey recent advances in the biomechanics of animal development and focus on our research on mechanical processes that shape the frog embryo. Using the elongating dorsal tissues of the Xenopus embryo, our group has developed a complete set of experimental tools and theory for direct biomechanical analysis of these movements. In this presentation I will discuss several surprising findings as we test the coupling between the processes that generate forces needed for extension and the processes that regulate spatial and temporal mechanical properties of the embryo. Forces and material properties can be coupled in a positive fashion that preserves rates of morphogenesis or can be negatively coupled to alter rates of morphogenesis in response to changing environmental conditions. Both mechanisms highlight basic elements of robust control networks that couple mechanics and cell signaling pathways and underlie morphogenetic programs that drive self-assembly. Dr. Lance Davidson is an Associate Professor and Wellington C. Carl Faculty Fellow in the Department of Bioengineering in the University of Pittsburgh’s Swanson School of Engineering.  He is an Adjunct Faculty Member in Developmental Biology and Computational and Systems Biology at Pitt and in Biomedical Engineering at Carnegie Mellon University.  Dr. Davidson is a Member of the Complex Biological Systems Group and a Member of the Interdisciplinary Biomedical Graduate Program - Molecular Genetics and Developmental Biology, University of Pittsburgh School of Medicine. Dr. Davidson received his BS degree in Physics from the University of Illinois at Urbana-Champaign in 1984 and his MSc degree in Experimental Space Science at York University in Toronto, Canada, in 1986.  He earned his PhD in Biophysics at the University of California-Berkeley in 1995.  He completed a postdoctoral fellowship at the University of Virginia in Cell and Developmental Biology.