A large number of plants growing in the rainforest are “aerial roots”. This describes a plant that grows in the upper regions and their roots are not in the soil  They are called epiphytes, which means they grow on other plants. The roots do not breath air, but extract the moisture in the air, like a sponge. This adaptation is because many plants need to grow in upper regions to get light that is not available on the forest floor. Plants like orchids, bromeliads, and ferns have these types of root systems.  They grow high in the canopy and the roots never reach the ground.