Terrestrial animal Terrestrial animal The term terrestrial is typically applied for species that live primarily on the ground, in contrast to arboreal species, which live primarily in trees. There are other less common terms that apply to specific groups of terrestrial animals: Terrestrial invasion is one of the most important events in the history of life. Terrestrial lineages evolved in several animal phyla, among which vertebrates, arthropods, and mollusks are representatives of more successful groups of terrestrial animals. Terrestrial animals do not form a unified clade; rather, they share only the fact that they live on land. The transition from an aquatic
Mars habitat Mars habitat A Mars habitat is a place that humans can live in on Mars. Mars habitats must contend with surface conditions that include almost no oxygen in the air, extreme cold, low pressure, and high radiation. Alternatively, the habitat may be placed underground, which helps solve some problems but creates new difficulties. One challenge is the extreme cost of building materials for Mars, which by the 2010s was estimated be about $2 million USD per brick to the surface of Mars. While the gravity on Mars is lower than that on Earth, there is increased solar radiation, temperature cycles,