Living organisms are capable of remarkable large-scale organization and coordination, as seen in fish schools, vegetation patterns, or microbial mats. How such organization occurs is an open question. It is hypothesized that organisms use a mix of shorter-distance and longer-distance interactions, such as physical contact and chemical communication, to organize and coordinate behavior. However, in most systems it is hard to identify and quantify these interactions. This project will reveal how feedback can modulate the ability to synchronize, coordinate, and form collectives, how groups tune key properties such as size and composition, and how groups control larger-scale pattern formation across multiple collectives. In the social amoeba, the types of interactions that coordinate behavior at both short and long distances are known. Studies of these amoeba will allow the development of methods to visualize these interactions and quantify them for the first time, during group formation. How these interactions work together to coordinate individuals across a single group and coordinate between multiple groups will be examined. The researchers will incorporate this empirical knowledge into a theoretical model to make general predictions. This project will train undergraduates, graduate students, and postdocs in research by involving them in the experimental and modeling projects. It will also train undergraduates in biological modeling via a course that will integrate concepts from this project.
Self-organization is pervasive throughout the biological world and understanding how it naturally occurs and the emergent patterns it produces constitutes the first step towards our ability to control such processes. Theoretical work has proposed that short- and/or long-range interactions and feedback between these interactions could drive self-organization, with different mixes of such interactions leading to different system-level consequences. Despite prolific theoretical work, experimental evidence for these proposed mechanisms has largely been lacking, primarily because there are few systems where we have the level of quantitative control and readout required. The researchers will address questions of self-organization and the resulting collective phenotypes in the cellular slime mold, Dictyostelium discoideum. Optimizing and exploiting new experimental techniques will permit quantification of the dynamics of short and long-range interactions. Combining the experimental techniques with a theoretical framework will help establish how the interplay between them leads to collective behaviors. This project will reveal how feedback can modulate the ability to synchronize, coordinate, and form collectives. The project may also determine how organisms tune key group properties such as size and composition, and control larger-scale pattern formation across multiple collectives.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
