Question

In the "arms race" between plants and herbivores, herbivores (insects) can overcome the toxic effects of plant specialized metabolites through natural selection. Which of the following would be an adaptation that would promote insect herbivory?
Plants express a novel gene that encodes for an inhibitor of larval development.
Insects express a gene coding for a new enzyme that degrades the plant toxin.
Plants develop a mutation that promotes the development of hairs and spines.
Insects evolve new taste receptors that trigger an avoidance reaction to the toxin.

Answer 1

Insects evolve new taste receptors that trigger an avoidance reaction to the toxin.

Explanation:

Plants are often fed upon herbivorous insects. to obtain protection against such attacks plant has developed several mechanisms like production of toxins and volatile substance that either kill the pest or attract the natural enemies of the insects respectively. To deal with these defense mechanisms, insects also developed certain characters such as the new taste receptors that trigger an avoidance reaction to toxins.