Why are the species considered dynamic groups and not static?

Explanation

### Step-by-Step Text Solution:

1. **Definition of Species**: A species is defined as a group of organisms that can interbreed and produce fertile offspring. This definition implies that species are not fixed entities but are subject to change over time.

2. **Sexual Reproduction**: One of the key factors that contribute to the dynamism of species is sexual reproduction. In sexual reproduction, genetic material from two parents is combined, leading to genetic variation among offspring.

3. **Genetic Variation**: The genetic variation that arises from sexual reproduction is crucial. It allows populations to adapt to changing environments and can lead to the development of new traits or characteristics within a species.

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