The olfactory pathway from the receptors to the cortex does NOT go through the thalamus. This suggests that the:
A) olfactory system evolved earlier than the other sensory systems did.
B) olfactory system evolved later than the other sensory systems did.
C) olfactory pathway came into existence after the thalamus developed.
D) the other sensory systems coevolved with the olfactory system.

Question

Quizplus · Accepted Answer

The olfactory system's direct pathway to the cortex, bypassing the thalamus, suggests it is an older evolutionary system compared to other sensory systems that do route through the thalamus. This indicates the olfactory system evolved earlier, allowing for direct processing of smells without the intermediary step of thalamic relay, which is seen in the later evolved sensory pathways.

The Olfactory Pathway from the Receptors to the Cortex Does