9781422277539

Caribbean Sea and the Gulf of Mexico are both part of the Atlantic Ocean, while the Bering Sea is part of the Pacific. The largest of the seas (the Mediterranean Sea) is about one-fifth the size of the small- est of the oceans (the Arctic). Together, the deep oceans and seas cover about 71 percent of the Earth’s surface, and make up by far the largest biome on the planet. Formed by the titanic geological forces that have shaped the conti- nents, their waters conceal dramatic submarine landscapes of deep trenches , high mountains, and active volcanoes. Oceans are not just broad puddles on the surface of the Earth. Their average depth is more than 2 miles (3.5 kilometers), while the average height of the land above sea level is just 3,280 feet (1,000 meters). In some places, underwater trenches plunge to depths of 6 miles (10 km) or more; such trenches could swallow Mount Everest A biome is a very large ecological area, with plants and animals that are adapted to the environmental conditions there. Biomes are usually defined by physical characteristics—such as climate, geology, or vegetation—rather than by the animals that live there. For example, deserts, rainforests, and grasslands are all examples of biomes. Plants and animals within the biome have all evolved special adaptations that make it possible for them to live in that area. A biome is not quite the same as an ecosystem, although they function in a similar way. An ecosystem is formed by the interaction of living organ- isms within their environment. Many different ecosystems can be found within a single biome. Components of most ecosystems include water, air, sunlight, soil, plants, microorganisms, insects, and animals. Ecosystems exist on land and in water, with sizes ranging from a small puddle to an enormous swath of desert. Biome versus Ecosystem

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Oceans