Plants have developed an array of chemical, mechanical and mimicry methods to fight off predators, meaning that they are not as defenceless as they seem.
- Plants have evolved defence mechanisms to ward off hungry grazers.
- Mechanical defences include spines and umbrella shaped canopies.
- Chemical defences like the toxic chemicals released by stinging nettles.
- Some plants mimic others and just pretend to have defences.
Plants cannot run away from predators but over millions of years of evolution, plants have developed complex defence mechanisms to deter or avoid them.
External structural defences that discourage herbivores are known as mechanical defences.
Mechanical defences: External physical adaptations
The acacia tree has developed long needle-spiked spines to deter grazers.
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