Here's why:
* The biological species concept (BSC) defines a species as a group of organisms that can interbreed and produce viable, fertile offspring. This concept relies on observing and studying reproductive isolation between populations.
* Extinct organisms cannot be directly observed for their reproductive potential. We can only infer their relationships based on fossil evidence and genetic analysis.
* While the BSC is useful for understanding evolutionary relationships, it has limitations. It doesn't apply to organisms that reproduce asexually or to species that are geographically isolated.
Therefore, the BSC is primarily used for studying and classifying living organisms. It provides a framework for understanding how species evolve and how they are related to each other.
However, for extinct organisms, we rely on other species concepts, such as:
* Morphological Species Concept: Classifying based on physical characteristics.
* Phylogenetic Species Concept: Classifying based on evolutionary relationships.
Ultimately, each species concept has its strengths and limitations, and the best approach often depends on the specific organism and the available data.
