Final answer:
Bright colors on insects indicating poison are known as aposematic or warning coloration, used by species like caterpillars and toads to warn predators of their toxicity.
Step-by-step explanation:
Bright colours worn by insects that are poisonous are known as aposematic coloration, or warning coloration. This is a type of defensive mechanism where poisonous or distasteful animals, such as certain caterpillars, fire-bellied toads, and many species of beetles, possess bright coloration to signal to predators to avoid consuming them due to their foul taste or toxic chemicals they contain. An example of an insect with this type of coloration is the monarch butterfly caterpillar which is bright yellow and black, warning predators of its toxicity. Aposematic coloration is effective because it relies on the ability of predators to see these bright colors and learn from their unpleasant experiences after attempting to eat these organisms.