Earth is often referred to as the blue planet because seas and oceans cover more than 75% of the Earth’s surface. Marine environments are therefore the most common habitat on Earth. Not only that, but water provides a 3-dimensional habitat which increases the available habitat for the animals, microbes, and plants to live.
Marine habitats are far different than terrestrial habitats for obvious reasons. Water provides a much different environment for organisms than the gaseous atmosphere of land-based environments. High concentrations of salt in seawater impact the physiology of living things found in the oceans. High salt concentrations can often be toxic to many organisms but marine species have evolved strategies to thrive in the salty environments.
Marine environments are not all the same and vary considerably in different areas. As the environments change so do the animals, plants, and ecosystems.
Coral reefs are tropical ecosystems created by tiny animals called corals. They are one of the most diverse and exciting ecosystems on Earth but an under severe pressure from global warming.
Rocky shores are coastal ecosystems controlled by the tides. Rocky shores are dangerous places to live but a wide range of invertebrate animals inhabit the rocks between the high- and low-tide lines.
The deep sea is one of the least explored environments on Earth but it covers around 60% of the Earth’s surface. Many strange and interesting creatures make the deep sea their home.