There are four layers of the Earth, including Inner Core, Outer Core, mantle, and Crust. Each layer has its characteristics because of its temperature and formation.
The inner core is solid with iron and other metal deposit in it. The outer core is liquid, while the mantle is composed of silicate rocks. The crust is the outer layer of the earth, consist of different types of rocks.
The earth was able to develop a layer structure because of the climatic change it had millions of years ago, where the hardest metal reached to its core.
The presence of a mountain range could isolate the gene pool of the species which would likely change or mutate characteristics may arise in the species. <span />
