Using cladistic analysis, a taxonomist wishes to construct a phylogenetic tree showing the relationships among various species of mammals. Which of the following would be the least useful for this purpose?

• A. Descriptions of various types of limbs (wings, legs, flippers, etc.)
• B. Data about skull bones
• C. The fact that teeth vary among types of mammals
• D. DNA base sequences
• E. The fact that all mammals have hair

Answer: (E)

Verified step by step guidance

1. Understand the concept of cladistic analysis, which is a method used to reconstruct evolutionary relationships by analyzing shared characteristics among species.
2. Identify the types of data that are useful for constructing a phylogenetic tree. These typically include morphological data (physical traits) and molecular data (DNA sequences).
3. Evaluate each option provided in the problem to determine its usefulness in cladistic analysis. Consider how each characteristic might reflect evolutionary relationships.
4. Recognize that shared characteristics that are common to all members of a group, such as all mammals having hair, do not help distinguish between different species within that group.
5. Conclude that the least useful characteristic for constructing a phylogenetic tree among the given options is the fact that all mammals have hair, as it does not provide information on the differences or evolutionary divergence among species.