The
prickles of a
rose plant.
Prickles, which are needle-like extensions of the
cortex and
epidermis, are often confused with
thorns, which are modified branches or
stems, and
spines, which are modified
leaves. All three are hard structures with sharp, pointy ends, which are generally used by plants to protect themselves from
herbivores. Thorns likely first
evolved as a defense mechanism in plants growing in sandy environments which provided inadequate resources for fast regeneration.
Photo: Noodle snacks