From above, the open ocean resembles a barren, lifeless, never-ending landscape.
But within the ocean's surface layer lie endless quantities of life.
This is the epipelagic zone, or sunlight zone.
Depth: 0m to 200m
Temperature: -2°C to 40°C
Within the sunlight zone, microscopic organisms such as plankton and algae can convert the Sun's energy through photosynthesis.
And where there are plants, there are animals.
Krill and small fish feed on algae and phytoplankton, in turn attracting larger predators, such as striped marlin, tuna, sailfish, dolphins, whale sharks and even birds, while manta rays siphon open water for food, such as fish eggs.
The open ocean provides little shelter from predators, but floating debris and seaweed can offer some protection.
And in places, the epipelagic zone's emptiness is broken by sea mounds – underwater mountains rising thousands of metres from the ocean floor.
Here, young fish have a place to grow in relative safety, while others come to breed.
Though it's never entirely safe. Predators such as hammerheads and silky sharks patrol these areas.
The epipelagic or sunlight zone is teeming with life. But just a few hundred metres below lies a very different world.