If you tried to pick a rose flower, it is highly unlikely that you have escaped without being pricked by its thorns. Sometimes it becomes very difficult and unpleasant to pick a flower from a thorny plant. There are many plants that have thorns.
All animals and plants have evolved and developed ways of defending themselves. Snakes and certain insects use venom to protect themselves. In the case of plants, they need to protect themselves from animals that would eat or injure them. Some plants have developed thorns to escape such animals.
Thorns come in various sizes and shapes. Do you know that the thorns of many plants, in fact, are modified branches? In some other plants such as cacti, they are modified leaves!
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