During the pre-ice age tertiary, the relatively warm, wet climate saw vast expanses of forest green across the continents, providing a habitat for wildlife. However, as the climate became colder and drier, the wildlife changed dramatically. Many species disappeared from the Earth, while others migrated to new habitats. While many new species specific to the Ice Age evolved, the whole landscape was transformed. The diversity of animals and plants declined during the Ice Age due to constant environmental stress, but the landscape became more diverse as new vegetation types emerged.

As for today, the environment shows signs of man’s transformations of nature.