What was the first animal on earth?

Was it a dinosaur? Or a mammoth? Neither! The first animal was probably an unassuming creature that lived in the ocean.

Multicellular organisms

The first living beings originated around four billion years ago. They were very simple creatures, a bit like bacteria. As they consisted of a single cell,you can’t really call them “animals”. You need more than one cell to earn that title. However, there are also multicellular organisms that aren’t animals, such as plants, many fungi and algae.

Animal traits

That’s why a creature has to have some more traits to be classed as an animal. For instance, an animal looks for and finds food, whereas a plant produces its own.

It was only around 600 millions ago that the first multicellular organisms with all these animal traits appeared – the first animals.

Sponge or comb jelly?

Still, scientists aren’t yet sure what the very first animal was. There are two candidates, both of which went extinct long ago. Yet they both looked like animals that live in our seas today.

The first was a type of sponge. Sponges live on the ocean floor and, as the name suggests, resemble the sponges you clean with. They’re not very interesting animals – with the exception of SpongeBob SquarePants, of course!

The second candidate is a type of comb jelly: a jellyfish that appears to have ribs. This sea creature, which is just as unexciting as the sponge, also doesn’t know how to swim!

Ancient traces

An ancient sponge or ancient comb jelly was probably the first animal on earth. Scientists hope to find ancient traces of these animals and finally solve the mystery of which appeared first. They might even come across traces of another, much earlier animal.

Answered by Yannick Fritschy