Terrestrialization can be thought of as the process that takes an aquatic organism, and through a series of adaptations and preadaptations, that organism evolves to a point where it can sustain itself on land.

This site will deal with the terrestrialization of vertebrates.  Other organisms like insects and scorpions also made a transition to land from the water, but it is unreasonable to try to tackle every single type of terrestrialization.

Throughout the text of the page, the words:  tetrapod, amphibian and terrestrial vertebrate will be used somewhat interchangably.
We will discuss the possible lineage for the first terrestrial vertebrates, the important fossil localities in this topic, (and why they are important), and the geologic sense of the process in terms of timing and relevant climate.

Overview of Terrestrialization