posted by Kim .
In some parts of the world bigger aquatic worms exist. These worms do not gain all of their oxygen through their skin. Suggest a reason for this.
Thanx kim xxx
Big suggests a higher activity level, so perhaps the rate of oxygen absorbtion through the skin cannot support the higher level of activity.
Exactly, transpiration is inefficent, only a certan thickness (mass/skin aerea) of creature can be supported by it