Do Cells Act Like Crowds?
Iain Couzin is an Assistant Professor in the Department of Ecology and Evolutionary Biology at Princeton University, where he manages the Couzin Lab. His research focuses on collective behavior and self-organized pattern formation in a variety of biological systems, including fish schools, bird flocks, insect swarms, human crowds, and cellular networks.
Question: Do cellular collectives behave like animal groups in any way?
Iain Couzin: Well, we are just beginning to start working on collective behavior at the cell level. We're sort of particularly inspired by some recent discoveries with soft body tumors and so we're very interested in issues of leadership and consensus decision making based upon our understanding of local rules. So although we started with animal groups and, you know, we work with animal groups extensively, I think these types of understanding actually allow us to get a different type of insight into cellular systems, and so this is a very new exciting sort of direction for my laboratory.
Question: What practical applications might this research have?
Iain Couzin: Well, we're certainly looking at cancer, we're interested in how and why collective migration is so common. So until relatively recently, it wasn't realized that, you know, collective behavior is so prevalent in soft body tumors. And now it's seen as one of the primary modes of spreading. And so that's something we want to understand.
And another very interesting aspect to tumors is the sort of the level at which selection is acting. So we're trying to simulate using new computational simulations, we're trying to simulate very large aggregates, where we can keep track of individual identities, we can look at mutations, we can see how this leads to individual behaviors that then scales up to a collective phenomenon. So as I mentioned, it's a new area for us. You know, we're still heavily working on animal groups, but it's very exciting to think that there really is this cross-understanding because the evolutionary principles and the principles of understanding how interactions scale to collective behavior, tend to be relatively universal.
Recorded on December 15, 2009
Interviewed by Austin Allen
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