Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Several animal groups have undergone aquatic adaptation, going from being purely terrestrial animals to living at least part of the time in water. The adaptations in early speciation tend to develop as the animal ventures into water in order to find available food. As successive generations spend more time in the water, natural selection causes the acquisition of more adaptations. Animals of later generations may spend the majority of their life in the water, coming ashore for mating. Finally, fully adapted animals may take to mating and birthing in water.

Данное издание не является оригинальным. Книга печатается по технологии принт-он-деманд после получения заказа.