Filness,according to Darwin refers ultimately and only to

Options

A. Dominance over others
B. Ability to defend
C. Strategy for obtaining food
D. Number of offsprings

Answer

**Step-by-Step Solution:**

1. **Understanding Fitness in Evolution**: The term "fitness" in the context of evolution refers to an organism's ability to survive and reproduce in its environment. It is not just about physical strength or dominance over others, but rather about how well an organism can pass on its genes to the next generation.

2. **Darwin's Perspective**: Charles Darwin introduced the concept of natural selection, which is the process through which certain traits become more or less common in a population based on their impact on reproductive success. According to Darwin, fitness is ultimately linked to reproductive success.

3. **Reproductive Fitness**: The key aspect of fitness, according to Darwin, is the number of offspring an organism can produce. Organisms that are better adapted to their environment tend to have more offspring, which increases their representation in future generations.

4. **Natural Selection**: This reproductive advantage leads to the concept of natural selection, where those individuals with traits that enhance their reproductive success are more likely to survive and reproduce. Over time, this can lead to evolutionary changes in a population.

5. **Conclusion**: Therefore, in Darwin's theory, fitness ultimately refers to the number of offspring produced by an organism, which is a measure of its reproductive success.

**Final Answer**: Fitness, according to Darwin, refers ultimately and only to the number of offspring.

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