The warm-temperate Mediterranean is one of the remnants of Tethys, the ancient ocean that once long ago allowed worldwide dispersal of tropical and subtropical marine organisms. Although most of that biodiversity vanished in the late Miocene, 5.5 million years ago, some Tethyan species still survive in the Mediterranean, as seagrasses whose closest relatives occur in Australia, and sturgeons related to those found in the Aral Sea. These survivors of Tethys share the Mediterranean with newcomers that colonized the basin after the last Ice Age, like the monk seal, the loggerhead sea turtle, and the sperm whale. This course will explore the origin and characteristics of this amazing biodiversity and the dynamics of the ecosystems where these species thrive. But the Mediterranean is also one of the most densely populated areas in the world and one of the most attractive destinations for European tourists. Overfishing, pollution, and destruction of coastal areas threaten the conservation of marine wildlife. The course will also consider the impact of these activities and whether sustained development can be achieved in the region.