The Following Questions Refer to This Hypothetical Situation

question 83

Multiple Choice

The following questions refer to this hypothetical situation:
A female fly, full of fertilized eggs, is swept by high winds to an island far out to sea. She is the first fly to arrive on this island, and the only fly to arrive in this way. Thousands of years later, her numerous offspring occupy the island, but none of them resembles her. There are, instead, several species each of which eats only a certain type of food. None of the species can fly, for their flight wings are absent, and their balancing organs (i.e., halteres) are now used in courtship displays. The male members of each species bear modified halteres that are unique in appearance to their species. Females bear vestigial halteres. The ranges of all of the daughter species overlap.
-In each fly species, the entire body segment that gave rise to the original flight wings is missing. The mutation(s) that led to the flightless condition could have

• A)duplicated all of the Hox genes in these flies' genomes.
• B)altered the nucleotide sequence within a Hox gene.
• C)altered the expression of a Hox gene.
• D)either A or B
• E)either B or C

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Definitions:

Axial Skeleton

The central part of the skeleton, comprising the skull, spine, ribs, and sternum.

Axial Skeleton

The central part of the skeleton, including the skull, spine, ribs, and sternum, that supports and protects the organs of the head, neck, and trunk.

Thoracic Cage

Also known as the rib cage, it encloses and protects the organs of the thorax, including the heart and lungs, while providing support for the shoulder girdle.

Vertebral Column

The backbone or spine, consisting of a series of vertebrae that protect the spinal cord and provide structural support.