Obstacles No Barrier to Higher Speeds for Worms, Courant Researchers Find

Obstacles in an organism’s path can help it to move faster, not slower, researchers from the Applied Math Lab at the Courant Institute of Mathematical Sciences have found through a series of experiments and computer simulations.

Their findings, which appeared in the Journal of the Royal Society Interface, have implications for a better understanding of basic locomotion strategies found in biology, and the survival and propagation of the parasite that causes malaria.

In the Journal of the Royal Society Interface study, Courant researchers sought to understand how efficiently undulating organisms can move through obstacle-laden fluids. To do so, they conducted a study comparing experiments using live worms, the nematode C. elegans, with the results of a computer model of a worm moving in a virtual environment. In the experiment, the worms swam through a very shallow pool filled with a lattice of obstructing micro-pillars while the computer simulation gave a benchmark of a worm moving blindly without sensing and response.

Surprisingly, C. elegans was able to advance much more quickly through the lattice of obstacles than through a fluid in which their movement was unimpeded. Another surprise was that the computer simulation gave very similar results, reproducing the fast motions of the worm in the lattice, but also showing complex “life-like” behaviors that had been interpreted as coming from sensing and response of the worm to its local environment.

These results enhance our understanding of biological locomotion through tortuous environments like soils or the reproductive tract, showing how real organisms can take advantage of what seems a defiant complexity, and offer intriguing insights into how the reproductive processes of dangerous parasites might be interrupted.

The study was funded by grants from the National Science Foundation and the Department of Energy.