Coral_Reef_Degradation

Coral Reef Degradation Fish are all heavier then water due to skeletons and other tissues containing heavy elements. Fish must find some way of staying buoyant in the water column, unless they are bottom feeders. A shark for example must be continually moving forward, yet they are aided in buoyancy by large livers, which contain a fatty hydrocarbon with a density less then water. Yet, the most effective means of buoyancy is the swim bladder, in which all bony fish posses. This swim bladder apparently arose from lungs on primitive fish, which were needed for such drastic wet and dry seasons in the Devonian era. Fish must continually be adjusting there swim bladders in order to prevent over-inflation or under-inflation caused by differences in water pressure at varying depths. There are two ways in which fish are able to adjust the gas volume, the first being a pneumatic duct which connects the esophagus to the swim bladder. Fish swim, gas, fish, bladder, water, must, rete, gland, yet, two, oxygen, network, mirabile, first, enters, depths, continually, containing, capillaries, buoyancy, blood, being, zoology, wet, ways, way, volume, varying, unless, under-inflation, types, traps, tissues, times, taking