It will decrees because required volume of blood will not be emptied into the pulmonary circulation to reach the lung for oxygenation. Rather blood flows back into the Right atrium ,(regurgitation,) through the these valves during ventricular contraction ( systole)of the Right Ventricle instead to the pulmonary circulation which reduces blood flow leading to volume overload in the heart. Eventually this affects systemic circulation,
Australia has so many genetically distinct organisms because it has been separated from other bodies of land for a very long time. This has given species in Australia a long time to evolve independently from species in other areas of the world.
