Water also exhibits viscosity. One can observe the effects of
viscosity alongside a stream or river with uniform banks. The water
along the banks is nearly still, while the current in the center may be
swift. This resistance between the layers is called viscosity.
This property allows smaller fish to live near the shore, while larger
fish are able to swim efficiently in strong currents. Viscosity is also
responsible for the formation of eddies, creating turbulence that
leads to good mixing of air in the water and more uniform distribution
of microscopic organisms.
How water provides all these properties are complex, but only
emphasizes the importance of water to every organism on Earth.