In the context of biological taxonomy, what do all organisms within the same taxonomic group (such as a genus or family) have in common?

• A. They occupy the same ecological niche.
• B. They always have identical physical characteristics.
• C. They share a common evolutionary ancestor.
• D. They are all capable of interbreeding with each other.

Answer: (C)

Verified step by step guidance

1. Understand the concept of biological taxonomy: Taxonomy is the scientific system of classifying organisms into hierarchical groups based on shared characteristics and evolutionary relationships. These groups include domain, kingdom, phylum, class, order, family, genus, and species.
2. Recognize that organisms within the same taxonomic group (e.g., genus or family) are grouped together because they share a common evolutionary ancestor. This means they have inherited certain traits from that ancestor, even if they have diverged in other ways over time.
3. Clarify why the other options are incorrect: Organisms in the same taxonomic group do not necessarily occupy the same ecological niche, as they may live in different environments or have different roles in their ecosystems.
4. Explain that organisms in the same taxonomic group do not always have identical physical characteristics. While they may share some traits, physical characteristics can vary due to adaptations to different environments or evolutionary divergence.
5. Highlight that organisms in the same taxonomic group are not always capable of interbreeding. Interbreeding is typically limited to organisms within the same species, not broader taxonomic groups like genus or family.