Darwin judged the fitness of an individual in term of -

Options

A. Dominance over the other individual
B. Strategy to obtain food and shelter
C. Keystone species
D. Differential reproduction

Answer

**Step-by-Step Solution:**

1. **Understanding Darwin's Concept of Fitness**:
- Darwin's concept of fitness refers to an individual's ability to survive and reproduce in its environment. It is not solely about physical strength but encompasses various traits that enhance survival and reproductive success.

2. **Adaptation to the Environment**:
- An individual’s fitness is judged based on how well it adapts to its habitat. The better an individual can utilize the resources and cope with environmental challenges, the higher its fitness.

3. **Reproductive Success**:
- The ultimate measure of fitness is the number of offspring an individual can produce that survive to reproductive age. This means that fitness is directly linked to the ability to reproduce successfully in a given environment.

4. **Survival of the Fittest**:
- This phrase encapsulates Darwin's theory, where "fittest" refers to those individuals best suited to their environment, not necessarily the strongest. It emphasizes that fitness is about the ability to survive and reproduce, leading to the continuation of one's genes in future generations.

5. **Conclusion**:
- Therefore, Darwin judged the fitness of an individual in terms of its ability to adapt to the environment and its success in reproducing viable offspring.

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