The deep-sea ecosystems include waters and sediments at the lowest layer in the ocean, existing below the thermocline and above the seabed, at a depth of 1000 fathoms (1800 m) or more. They represent the world's largest biome, covering more than 65% of the world surface and including more than 95% of the global biosphere. This book examines the marine biology, geology and human impact of the deep-sea environment. Topics discussed include the stratigraphical distribution and evolutionary classification of the schackoinid planktic foraminifera; the biological characteristics of the skilfish, erilepis zonifer in the North Pacific Ocean; protein degradation at deep-sea sediment; primary production and carbon cycling in the deep-sea; and biodiversity and ecosystem function in the deep-Mediterranean Sea.