Soft bodied animals like caterpillars often fall a prey to voracious hunters like birds or reptiles. Despite having no means to 'actively' defend themselves, with weapons like claws or jaws, they have nevertheless, evolved other equally effective deterrents. A particular species of the caterpillar lives at an altitude over 2.500 metres in the Himalayas. It uses prominent colour to inform would be predators of its in edibility. In the event that an inexperienced or adventurous bird did eat the caterpillar, it would probably vomit it soon after, and subsequently desist from attacking similar species in future. Though this would do the unfortunate victim no good, the species benefits. A rare example of the martyr among animals.

The expression "others equally effective deterrents'' mean