Numerical taxonomy which is now easily carried out using computers is based on _____

Answer

**Step-by-Step Solution:**

1. **Understanding Numerical Taxonomy**: Numerical taxonomy is a method of classifying organisms based on measurable and observable traits. It uses a systematic approach to categorize living organisms.

2. **Role of Computers**: With advancements in technology, computers are now used to perform numerical taxonomy efficiently. They can handle large datasets and perform complex calculations quickly.

3. **Observable Characters**: The foundation of numerical taxonomy lies in observable characters. These are traits that can be measured or observed, such as morphology, behavior, and genetic information.

4. **Assigning Numbers and Codes**: In numerical taxonomy, each observable character is assigned a numerical value or code. This allows for a standardized way to analyze and compare different organisms.

5. **Equal Importance of Characters**: In this approach, each character is treated with equal importance. This means that no single trait is prioritized over another, allowing for a more balanced classification.

6. **Inclusion of Multiple Characters**: Numerical taxonomy can incorporate hundreds of observable characters, providing a comprehensive view of the organisms being studied.

7. **Conclusion**: Therefore, the answer to the question is that numerical taxonomy, which is now easily carried out using computers, is based on observable characters.

**Final Answer**: Observable characters.

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