In biology, to what does the term fitness refer?

Step by Step Solution: Step 1. Fitness in biology refers to an organism's ability to survive and reproduce in its environment. Step 2. Fitness is often measured by the number of offspring an organism produces that can also reproduce and pass on their genes to their own offspring. Step 3. This concept is a key component of the theory of natural selection. Step 4. Individuals with greater fitness are more likely to survive and pass on their genes to the next generation. Step 5. Therefore, over time, the traits that contribute to greater fitness become more common in a population. Final Answer: Fitness refers to an organism's ability to survive and reproduce in its environment.