Achievement

Trainee David Smith (Biology) spent Spring 2011 at Mt. Bachelor, OR (altitude ~3 km), sampling dust in air that crossed the Pacific Ocean from Asia. Millions of bacterial and fungal microbes are embedded in each gram of dust. Their survival depends largely on remaining dormant or receiving protection from dust grains or layers of surrounding dead cells. David confirms a fraction of bacteria and fungi survive long-distance, upper-atmospheric transport in this manner. Germination of these cells landing in distant environments could profoundly effect marine and terrestrial ecologies. Presumably, microbes have the potential to introduce foreign genes into novel environments or activate newly-inherited, ultraviolet radiation-induced mutations. David’s work characterizes this airborne transport mechanism that could help explain why everything is everywhere in microbial biogeography, and provides a new definition for the boundary of Earth’s biosphere, at altitudes bordering the edge of space.