9.6: Defense

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Predation, warnings, and deception.JPG — Figure \(\PageIndex{1}\). *Predation, warnings, and deception.*

Prey develop remarkable defenses against predators, following the processes of evolution, and provide warnings of the existence of their defenses. Some such defenses and advertisements are real, like the fetid fluid sprayed by skunks (Figure \(\PageIndex{1}\) left) that can deter even large bears from attacking. The fire-bellied toad (next to left) is filled with toxins and its bright color advertises, “Do not eat me!”

Others species benefit from complex deception to keep predators away, such as the harmless clear-winged moth colored to look anything but harmless (next to right), and an edible caterpillar in disguise with a viper-like tail (right).

Predation, camouflage, and temptation.JPG

Hiding is a simple, common strategy for escaping predators. On the left in Figure \(\PageIndex{2}\) is a young grasshopper on pebbles. Can you see it? Zoom in and look just a little below and to the left of center. The grasshopper’s head is downward and its tail is upward and slightly to the left, with one antenna and one leg clearly visible once you see them.

The killdeer (Figure \(\PageIndex{2}\), right) tempts predators who get too close by stumbling away from the nest, feigning an injured wing and making itself look like an easy catch. Once it has lured the predator far from the nest, it lifts quite competently into the air and flies off.