Why are there usually so few organisms at the top level of a pyramid of energy?

The kidneys, ureter, bladder, and urethra the body maintain homeostasis through the process of a. excretion b. specialization c. respiration d. digestion

Texas has an impending storm, and california is experiencing a water crisis. match the technologies with the state that can use them to reduce the effects eddies natural hazards. texas is the storm cellar and the wood that is crisscrossed. california is the dam and the storage tanks

Is there any species that went extinct in recent years due to natural causes (not caused by human interaction). if so, what caused it?