Invertebrates are a group of animals that do not have a back bone. Mammals, amphibians, reptiles, fish and birds do not fit into this category because they all have vertebrae (spinal bones), but these animals make up less than 4% of all the animal species on Earth. This means that around 96% of animal species alive are invertebrates. These include marine invertebrates and molluscs, such as sponges, jellyfish and oysters, as well as crustaceans and insects, such as crabs, shrimp and butterflies.
The largest invertebrate ever recorded was a giant squid that measured 13m long. The smallest invertebrates are so tiny that they cannot be seen by the naked eye.
Write a short definition of the word ‘invertebrate’, using your own words.
What percentage of animals on Earth actually have spinal bones?
Who do you think this information is for? Why?
Write two questions that you could find the answers to in this text.