ELI5: Explain Like I'm 5

All Species Foundation

Okay kiddo, do you know what a species is? It's a group of living things that are similar to each other in lots of ways, and can have babies that are also part of the same group. So, for example, dogs are a species because they all look and act like dogs, and can make more dogs when they have puppies together.

Now, imagine that all the different species of plants and animals on Earth are like a big family tree. At the very beginning of this tree, there was just one type of living thing that started it all. Scientists call this the "all species foundation", because it's like the foundation or base of the whole tree.

Over time, different groups of living things evolved or changed in different ways, and split off from each other to become their own species. This is kind of like different branches growing from a tree trunk. Some of these branches might have new and different characteristics, like feathers or fins or leaves, while others might have kept a lot of the same traits as their ancestors.

But even though there are now millions of different species all over the world, they all came from that one original foundation – just like you might have lots of cousins and relatives, but you all share the same family history and background. It's a really cool idea to think about, and helps us understand how all living things on Earth are connected in some way!