1. The female mackerel lays about 500,000 eggs at a time!
2. Fish have been around for more than 450 million years and were well established by the time of the dinosaurs.
3. There are over 25,000 identified fish species on the planet with an estimated 15,000 still to be discovered. That's more than all the species of amphibians, reptiles, birds and mammals combined!
4. Fish have excellent senses of sight, touch, taste and many possess a good sense of smell and 'hearing'.
5. The oldest known goldfish lived to 41 years of age. Its name was Fred! The oldest fish ever recorded was a female European eel, who was 88 years old when she died at Halsingborg Museum, Sweden, in 1948.
6. Piranha bodies are covered in so many tastebuds that when something floats passed, they can tell if its worth eating or not!
7. Octopus are great escape artists; an adult octopus can squeeze through a hole not much bigger than a 10p coin.
8. The Seahorse belongs to the Syngnathidae family, the only group of animals where the male becomes pregnant and giving birth anything from 20 to 400 babies!
9. The fish that produces most eggs is the ocean sunfish, which produces up to 30 million eggs at one single spawning.
10. There are over 11,500 fish and chip shops all over the UK. These shops sell 250 million portions of fish and chips each year.