Metabolic equilibrium actively maintained by several complex biological mechanism nervous system
The correct answer is the second option. Animals have two major types: vertebrates and invertebrates. Vertebrates are animals that have backbone while the invertebrates do not have one. Examples for vertebrates are birds and mammals while the latter are insects and squid.
Answer AND Explanation:
The islands had different environments, and the organisms had adaptations that enabled the organism to live in those environments. The island had been inhabited by its own kind of species found nowhere else in the world. Darwin also noticed that considerable variation exists between members of the same species. Offspring vary from their parents and between themselves.
