Final answer:
Warning coloration is effective against vertebrate predators with vision that can learn and avoid prey based on color signals indicating toxicity or bad taste, exemplified by organisms like the monarch caterpillar and fire-bellied toad.
Step-by-step explanation:
Warning coloration, also known as aposematic coloration, is most effective against vertebrate predators that rely on vision to locate prey and have the ability to learn from experience. A classic example is the monarch butterfly caterpillar, which absorbs toxins from its diet of milkweed to become poisonous or distasteful, communicating this danger through its bright yellow and black coloration.
Similarly, the fire-bellied toad has bright belly coloration to indicate its toxicity, deterring attacks from would-be predators. When a harmless species mimics the warning coloration of a harmful one, a phenomenon known as Batesian mimicry, it benefits by deceiving the same vertebrate predators without possessing the actual defenses.