The vertebrate record for most offspring has been set by the oceanic sunfish, which can produce a staggering 300 million eggs at a time
These fish can reach 3.2 metres (10.5 feet) in height and live for 10 years. They spend most of their time basking in the warm sun that penetrates the top few metres of the sea, but dive deep to hunt jellyfish up to 40 times per day. The deepest recorded dive for this enormous fish is just under 650 metres (2100 feet), but sunfish need to surface quickly to warm up.
Sunfish produce an enormous volume of eggs and release them into the open ocean for them to be fertilised by sperm released by a male.
When the eggs hatch, spiny sunfish larvae are less than three millimetres (0.1 inches) long and are unable to propel themselves. They feed on smaller plankton and resemble a miniature puffer fish for half their lives before going through a phase of rapid transformation into their giant forms.