The Figure Below Shows the Vertebrates and Arthropods to Be

question 23

Multiple Choice

The figure below shows the vertebrates and arthropods to be distantly related, yet each has features, like limbs and jaws, seen in no other groups.
How can such an obvious similarity be discounted in favor of embryological development as a basis for classification?

• A) The decision to overlook certain features reveals the arbitrary nature of classification and explains why there is so little agreement among taxonomists.
• B) Limbs are not discounted by taxonomists; they were acquired from a common ancestor but later lost by the mollusks, annelids, and echinoderms.
• C) Embryos are securely protected during development and have little need to evolve; shared inherited features indicate a common ancestor.
• D) Examination of the embryos of all animals with body cavities reveals limbs, but they are unnecessary for some lifestyles and so they degenerate.

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Definitions:

Caudate Nucleus

A structure within the brain involved in various processes such as voluntary movement coordination and learning.

Lateral Fissure

A deep groove on the surface of the brain separating the temporal lobe from the frontal and parietal lobes.

Cerebrum

The cerebrum is the largest part of the brain, responsible for cognitive functions such as thought, memory, and decision-making.

Temporal Lobe

A region of the brain located on the sides of the cerebral hemisphere, involved in processing auditory information and encoding memory.