The smallest unit that can evolve is

Options

A. A geonome
B. An individual
C. A species
D. A population

Answer

**Step-by-Step Solution:**

1. **Understanding Evolution**: Evolution refers to the process through which species undergo changes over time due to genetic variations and natural selection. It is important to clarify the unit at which evolution occurs.

2. **Identifying the Units of Evolution**: The potential units that can be considered for evolution include:
- Genome
- Individual
- Species
- Population

3. **Evaluating Each Option**:
- **Genome**: While mutations can occur at the genomic level, evolution does not occur at this level alone. Changes in the genome must be passed on through generations to affect a population or species.
- **Individual**: An individual organism does not evolve by itself. Evolution is a process that affects populations over generations, not individual organisms.
- **Species**: A species is a group of organisms that can interbreed and produce fertile offspring. Evolution occurs at the species level as populations of a species adapt and change over time.
- **Population**: A population is a group of individuals of the same species living in a specific area. Evolution can be observed in populations as genetic variations spread through generations.

4. **Conclusion**: The smallest unit that can evolve is the **species**. Evolution occurs at the level of populations within species, not at the individual or genomic level.

**Final Answer**: The smallest unit that can evolve is a **species**.

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