Why is this animal unusual?
A female can carry 300 million eggs – more than any other animal with a backbone. A newly hatched sunfish is the size of a pinhead and may grow to 60 million times that weight.
Why does it look like that?
Where other fish have a tail, the sunfish has a stiff, wavy flap. It swims by flapping its top and bottom fins from side to side, like a bird turned sideways.
Strangest biological feature
A beak. Its teeth are fused into a parrot-like plate, and it can’t fully close its mouth.
Why is it strange?
It sunbathes. After deep, cold dives it lies flat at the surface to warm up – and lets seabirds peck the parasites off its skin.
Interesting behavioral facts
Despite looking helpless, it’s a strong swimmer that travels long distances and dives hundreds of metres to hunt.
Records held
One of the heaviest bony fish in the world. Its close relative, the giant sunfish, holds the outright record: one found in 2021 weighed 6,000 lb (2,744 kg).
