Succulent
having fleshy tissues designed to conserve moisture (A3, C2)
Exoskeleton
an external supportive covering of an invertebrate (A3)
Endangered
in immediate danger of becoming extinct (A3, C4)
Adaptive radiation
the rapid development of many species from a single ancestral population (A3, R2, R3, IS1)
Adaptation
a change in an organism or species that enables it to survive in a particular habitat (A3, C3, R3, M2, M3)