What are common features of all rainforests?

Though rainforests can be found in a variety of climate zones, they all have several features in common, including the fact that there is a rainforest on every continent on earth (except Antarctica) and they are all essential providers of natural resources, including water. Additionally, rainforests can be characterized by their layers, which include, from top to bottom, the emergent layer, the canopy, the understory and the forest floor, each of which has its own unique characteristics.

Rainforests across the globe are threatened by human activities such as logging, ranching, farming and mining; only about 50% of the initial scope of rainforests still exist, according to the Nature Conservancy.