humanity of the year 3001 worthy of survival, or at least not a threat to the Europans. Their assessment seems to prove true, as subsequently Frank Poole and the other humans land on Europa and attempt to start peaceful relations with the primitive native Europs. Europs When TMA-2 transformed Jupiter into the new star "Lucifer", it warmed Europa to nearly the average temperature of Earth, melting the ice sheets which once covered the moon - and giving an evolutionary boost to indigenous life-forms which had existed in the oceans hidden beneath. This is directly compared to how the original TMA-0 gave pre-human apes an evolutionary nudge on the path towards sapience. The near-sapient life-forms on Europa are dubbed "Europs" by humans. Due to the branching storylines of each book, the third novel ends with a flash-forward 20,000 years into the future, with the Europs developing a basic civilization without outside contact from humanity. The fourth and final novel, 3001, altered this to end with the revived Frank Poole making first contact with the Europs and attempting to begin peaceful relations. Physically, Europs are described as looking like "a small, leafless bush, with no obvious sense organs or means of communication". They walk on half a dozen slender trunks, which divide into hundreds of twigs, which divide again - making them very dexterous, and potential tool-users. Prior to the Monoliths' interference, they evolved as filter-feeders on the frozen seas under the moon's ice, using their twig-arms to strain for plankton. They were hunted by predators, one notable species of which is described as "like a flying carpet, but as big as a football field", dredging the ocean floor. In response, the Europs gradually evolved to build basic shelters for themselves on the ocean floor - comparable to Earth cephalopods using shells as "tools" in the form of protection. The Monolith's warming of the moon spurred the Europs to become amphibious, migrating on land where they construct basic ice-igloos, as an advancement from their underwater hovels. The Europs still need to return to water to feed, but now have total protection from aquatic predators while they sleep in their land-based shelters. Because life in Europa's oceans evolved around thermal vents that received no sunlight, the Europs' biochemistry is based on sulfur respiration. This is much less energy efficient than the Terran biosphere's oxygen-based respiration, resulting in the Europs being very slow: it's