Thinking about... fossils

You have probably heard lots of different things about what the Earth was like millions of years ago. You may have read there were animals, like dinosaurs, that lived then that were much different than animals living today. And that there were seas and beaches where today there are deserts. And mountains where today there are plains. But I don't know of anyone who was alive that long ago! Do you? So how do we know ANYTHING at all about what the Earth was like in the far distant past and what living things existed thousands and millions of years ago? Fossils help scientists figure all of this out! Plus – fossils are just cool to collect and look at.