Phylogenetic system differs from a natural system in its stress on

Options

A. Anatomical details
B. Physiological traits
C. Morphological details
D. Origin and evolutionary trends

Answer

To solve the question "Phylogenetic system differs from a natural system in its stress on," we will analyze the options provided and understand the key differences between phylogenetic and natural classification systems.

### Step-by-Step Solution:

1. **Understanding Phylogenetic System**:
- The term "phylogenetic" relates to the evolutionary history and relationships among organisms. It emphasizes how species have evolved over time from common ancestors.

2. **Understanding Natural System**:
- The natural system of classification focuses on the observable characteristics of organisms, such as their morphology (shape and structure), anatomy, and physiology, without necessarily considering their evolutionary relationships.

3. **Analyzing the Options**:
- **Option 1: Anatomical details** - This refers to the internal structures of organisms. While important, it is not the primary focus of the phylogenetic system.
- **Option 2: Physiological traits** - This relates to the functions of the organs and systems within organisms. Again, this is not the main focus of phylogenetic classification.
- **Option 3: Morphological details** - This pertains to the external features of organisms. While morphology can provide some insights into evolutionary relationships, it is not the central theme of phylogenetic classification.
- **Option 4: Origin and evolutionary trends** - This option directly relates to the evolutionary history and the relationships between different organisms, which is the core of the phylogenetic system.

4. **Conclusion**:
- Based on the analysis, the phylogenetic system differs from a natural system primarily in its emphasis on "origin and evolutionary trends." Therefore, the correct answer is **Option 4**.

### Final Answer:
**The phylogenetic system differs from a natural system in its stress on origin and evolutionary trends.**

---