My lab uses human pluripotent stem cells to study the developmental mechanisms underlying formation of embryoids and organoids in vitro, and by extension, embryos and organs in vivo. We take an interdisciplinary approach, combining cutting edge biology and engineering tools to manipulate cells, and computational methods to analyze and interpret live cell image data. Specifically, we focus on: Interpretation of rapidly changing signals during differentiation. Morphogens are diffusible signaling molecules thought to determine cell fates in a concentration-dependent way, but this static model is insufficient for the vertebrate embryo, where differentiating cells experience rapidly changing morphogen levels. We simultaneously measure signaling activity in thousands of individual cells during differentiation in order to understand how spatial and temporal patterns in signaling activity form and are related to cell fate. One of our exciting and unexpected findings using this approach is that for some developmental signals, the cell response depends more on the rate at which a signal changes than on the absolute signal strength. Interplay between intercellular forces, shape, and paracrine signaling. Tissue patterning and shape are closely tied together. The same signals that specify cell fate affect tissue shape by regulating cell growth, motility and contractility. Conversely, mechanical and geometric constraints modulate signaling and affect pattern formation. We combine live imaging of signaling and cytoskeletal dynamics with mechanical manipulation and force inference at the single cell level to understand this interplay.