Question
The evolution of photosynthesizing organisms on Earth and the development of an oxygen-rich
environment led to a rapid diversification of life. Explain why there is an evolutionary advantage
to an organism that requires oxygen to live compared to one that does not require oxygen.
Answer
Organisms that require oxygen to live have an evolutionary advantage because they can access more energy from their environment than organisms that do not require oxygen. Oxygen is a more efficient electron acceptor than other molecules, allowing organisms to produce more energy from the same amount of food. This increased energy availability allows organisms to grow and reproduce more quickly, giving them an evolutionary advantage.