We live on a blue planet. About 71% of the Earth’s surface is covered in water, and a whopping 97% of this is found in our seas and oceans.
However, we still know surprisingly little about this watery realm – so far, only 5% of our oceans have been explored. What we do know is that life under the waves is as rich, varied, and fascinating as life on land.
The majority of marine life is concentrated along the continental shelves – the shallow waters surrounding the major land masses. Here, sunlight and nutrient upwellings create an ideal environment for plants and algae to thrive, which in turn support vast food chains from tiny zooplankton right up to the mighty blue whale: the largest animal ever to have lived on Earth.
Around the tropics we find coral reefs, which are among the most biodiverse ecosystems on the planet. Despite occupying just 1% of the seabed, these support more than a quarter of all marine life.
Yet even if we venture out of these biodiversity hotspots, down into the deepest abysses or to the frigid waters of the poles, we still find an astonishing variety of life – much of it bizarre, and all of it extraordinary.