Death because it decreases the population
I'm not exactly sure of your question but here's what i think your asking, Darwin and scientists today have discovered that the ancient organisms whose remains they find look like organisms alive today because they are the living organisms' ancestors or evolved from a common ancestor. They provide valuable information about evolution and how life formed
Enzymes are biological catalysts which speed up the speed of reaction by lowering the activation energy without itself being consumed for e.g to digest proteins there are dfrn enzymes and to digest carbohydrates there are dfrn enzymes every enzyme is specific in its function