We present a series of experiments on the survival abilities of terrestrial and flying insects in the rain.  Social insects such as fire use their bodies to weave hydrophobic rafts in the manner of GoreTex.  We report on their method of self-assembly and present a mathematical model that predicts their construction rate.  Mosquitoes and other small flying insects repel raindrops by virtue of the insect’s relatively small inertia.  Raindrops apply glancing blows to the insects, spinning or pushing them in mid-flight, rather than splashing.  We rationalize the water-repellency of these systems using basic principles such as momentum and energy conservation and Cassie and Wenzel laws of water-repellency.  Particular attention is paid to re-defining water-repellency in terms of active behaviors (weaving) and passive properties (surface texture and body mass).

Biography
Dr. David Hu is an assistant professor of mechanical engineering and biology at Georgia Tech.  Previously, he served as an instructor of mathematics at New York University and as an undergraduate and graduate student at MIT.  His research group performs simple table-top experiments aimed at elucidating fundamental physical mechanisms in biological systems.  Their work has been featured in The Economist, Nature, The New York Times, Discovery Channel, National Geographic, and Good Morning America.