Qing (Andie) Zhang, Ph.D., Postdoctoral Researcher, Stanford University

Speaker:

Qing (Andie) Zhang, Ph.D.

Postdoctoral Researcher

Stanford University

Faculty Host: Michelle O'Malley

Title: Multiscale mechanics in living ecosystems

Abstract: 

Living ecosystems, from sea ice to coastal mudflats, are dynamic landscapes shaped by the interplay of physical forces and biological activity. To predict and engineer functions in these systems, a central challenge is connecting micro-scale cell mechanics with emergent, macro-scale patterns. In this talk, I will present cross-scale frameworks to bridge this gap, integrating complex fluids, cell biology, and microbial ecology. I will first introduce a physical model system demonstrating how microscale nematic alignment steers macroscopic pattern selection, establishing a process-to-pattern foundation. I then extend this physical lens to two critical ecosystems at liquid-solid interfaces. In sea ice, I will discuss our discovery of a unique ice-gliding motility in ice-dwelling diatoms during a 45-day Arctic expedition, revealing how these cells actively navigate porous sea ice in extreme cold and establishing the record-low temperature limit for eukaryotic cell motility. In coastal mudflats, I will show that diatoms self-organize into ecosystem-scale active nematics. These communities utilize mechano-chemical trigger waves to coordinate directional movement and deposit mucilage to imprint mechanical memory, enabling rapid recovery after disturbance. Together, these results decode how living matter adapts to and re-engineers its habitat and motivate an ecosystem-inspired engineering paradigm for environmental resilience, energy sustainability and self-healing material design.

Bio:

Qing (Andie) Zhang is a Postdoctoral Researcher in the Department of Bioengineering at Stanford University. She obtained her Ph.D. in Mechanical Engineering from MIT. Her research lies at the interface of complex fluids, cell biology, and microbial ecology, focusing on multiscale mechanics and the control of pattern formation in complex and living systems. Combining laboratory experiments, theoretical modeling, and field research including Arctic and Pacific Ocean expeditions, she bridges cell-scale dynamics and landscape-scale organization in sea-ice and coastal mudflat ecosystems. Her work lays a physical foundation for understanding niche construction and developing new engineering tools for environmental and energy challenges.