Rapid City in South Dakota has a rich diversity of fossil remains. “Back in the day” could reference anywhere from 500 million to 50 million years ago!
Cretaceous marine life existed around 75 million years ago, give or take two weeks. If you could stop your time machine around then, you might take a dip with long-necked plesiosaurs! Once it was time to get out of the water, you might see a Duckbilled Dino.
Skipping through the years, you might see other sights…
If your time machine stops at 150 million years ago, you might want to stay inside and just look out the windows at the gigantic dinosaurs from the Jurassic Period. The Apatosaurus may be pontificating about not being consulted when its name was changed from Brontosaurus. The Allosaurus may be out for a jog. Your time machine does have windows, right?
Otherwise, we may be looking for your fossil remains!
“It isn’t easy to become a fossil. … Only about one bone in a billion, it is thought, becomes fossilized. If that is so, it means that the complete fossil legacy of all the Americans alive today – that’s 270 million people with 206 bones each – will only be about 50 bones, one-quarter of a complete skeleton. That’s not to say, of course, that any of these bones will ever actually be found.” —-Bill Bryson
Buy it. Read it. Let me know what you think. –TMLL