Weird giant sunfish reveals secrets

We finally know why a huge, odd and enigmatic fish likes to sunbathe

Presented by

Melissa Hogenboom

The face of an ocean sunfish certainly leaves an impression.

So too does its size; they are the largest bony fish in the world, ranging from one to four metres across, and weighing up to a tonne.

And their name?

They are called sunfish because they spend almost half their day basking motionless at the ocean's surface, seemingly catching some rays. 

But until now it was not understood why they sunbathed, or exactly what they get up to in the deep ocean.

Read on ...