We consider two aspects of flight, host-finding by mosquitoes and feather maintenance by birds.  Mosquitoes are known to use various cues such as vision and carbon dioxide to track down their hosts.  We use 3D cameras to measure mosquito flight trajectories around inanimate objects and use Bayesian inference modeling to predict their behavior around a human exhibiting a combination of cues. Next, we ask why birds bathe.  We consider the aerodynamic effects of bathing in water and shaking dry.  Feathers block wind by the interlocking of microscopic barbs.  We show how these feathers become more robust through coatings in the bird's oil glands and collisions between barbs that “heal” a feather and prepare it for flight.