Flies Have Only a Single Pair of Functional Wings, but Their

question 97

Short Answer

Flies have only a single pair of functional wings, but their ancestors had two pair of wings. Thus, having two pairs of wings is a(n) _______ trait.

---

Definitions:

Articular Surface

The surface of a bone that comes into contact with another bone to form a joint, facilitating smooth movement between them.

Facet

A small, smooth, flat surface on a bone, often where two bones articulate.

Bone Marking

Features on the surface of bones, such as ridges and depressions, that serve as sites for attachment of muscles, tendons, and ligaments.

Rough Projection

Refers to a bony projection with a rough surface, often serving as a site for muscle attachment.