Water properties

Coloured Water

No! I am not talking about American beer but about ordinary clean water, water that should come out of your tap. From the air, shallow coastal sea-waters above white sands often appear to be blue or green, most of this colouring being due to either reflection from the sky or from organic growths such as chlorophyll containing algae.


We have written much here in this magazine about the different properties of water. Some of them, such as surface tension, are of importance to the ability of aquatic fauna to function in their given environment. For example, surface tension permits water skaters to skate on the surface of the water where its habitat is neither the water below the surface nor the air above.


Aquatic animals, like their land-based relatives, can communicate in a number of ways. For example, in one form of communication, organisms can emit and detect certain organic molecules which can function as the pheromones of land based creatures. This is a sexual communication.