Coping with danger
Animals
Animals may have individual or social defence behaviours that allow them to avoid danger from predators. This avoidance behaviour or escape response is usually an unlearned behaviour that will protect an organism.

Habituation is a short-term energy saving behaviour. It occurs when a stimulus is found to be harmless and the organism will cease to show the escape response. Long term modification of this type would result in the organism becoming vulnerable to predators.

Learned behaviour is a long-term modification that develops when an animal has found an alternative behaviour to be of advantage e.g. a toad stung by a wasp will refuse yellow and black food because it has learnt it means danger.

Individual mechanisms of defence may be active, such as an octopus squirting ink, or passive such as a stick insect resembling a twig and therefore being camouflaged.

Social mechanisms tend to involve a group working together to confuse or startle the enemy.

Plants
A plant, being sessile, must have different strategies of defence. To avoid being eaten by herbivores a plant may have stings, thorns or spines. Some plants have other adaptations that allow them to survive grazing, such as low meristems, deep root systems or an underground stem/ foodstore. They minimise damage and regenerate quickly.