|MadSci Network: Zoology|
It all depends on what you mean by a nose. If you mean a projection from the head through which the animal breathes and smells odours, like a mammal nose, then the answer is no. Insects are less cephalised than mammals. This means that their important sensory organs are not clustered upon the head to the same extent as they are in a mammal, some sensory organs may be distributed along the body or on the feet. Caterpillars can smell and taste their environment, which they need to do in order to find their food plant, and stay on it. On their heads, around the mouthparts, most caterpillars have chemoreceptive sensilla, organs sensitive to certain chemicals similar to our taste buds or the sensory nerve endings in our nose. They breathe through spiracles, small holes along the sides of their body which connect to a network of air tubes distributing oxygen throughout their body. Caterpillars do not have a nose in the same sense as you or I, but they do have the same abilities to taste, smell and breathe through organs distributed around their bodies.
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