Conditions Governing the Distribution of Insects in the Free Atmosphere

Insect collecting by aircraft (1) has shown that individuals of some species of insects attain heights of four or more kilometers above the earth (6). Upon consideration of the meteorological conditions within this vertical range, it would seem that the normal decrease with height of atmospheric pressure, temperature and humidity would bar flights to altitudes such as those at which specimens have been found. Conversely, certain atmospheric processes might act to carry insects inertly to such altitudes, possibly beyond the supposed limits of insect resistance to the first-named elements.