Asymmetric burrow openings create passive ventilationprairie dog
Differences in position and shape of burrow openings of black-tailed prairie dogs create passive ventilation from wind energy by altering air pressure.
Mound facilitates gas exchangemound-building termites
The structure of above-ground macrotermite mounds facilitates gas exchange in the below-ground nest using internal air currents driven by solar heat.
Shapes cover curved surfaces efficientlytortoise
The shell of tortoises optimizes material use for a curved surface via hexagonal subunits and filler shapes.