Time once again for the A Moment of Science Big and Bad File. This is where we tell you about anything that sets a record. Today's Selection from the Big and Bad File is...the world's oldest footprint!
Now, I know you weren't expecting that. We think of footprints as pretty ephemeral--you walk through a dusty field, leave some marks, and by next afternoon they're gone. How old could the oldest one possibly be?
Well, suppose you walked through something that keeps prints better than dust. Say you walked through some drying concrete. That print might still be there decades later. Right?
Now try this. You're walking through an area of still-cooling ashes and rock bits that came out of an active volcano. All of a sudden the volcano erupts again. You run away from the spewing lava. A new layer of ash and fragments flows over the layer that holds your footprints, effectively sealing them in.
This is just what seems to have happened to some people who lived in what is now the Rocammonfina Complex of southern Italy. It wasn't Italy then, though; these prints are around three hundred and fifty thousand years old. The print-makers were people of the Paleolithic era--what are commonly known as "old stone age" people. Based on the tracks, they were probably about five feet tall and were running, possibly from the second eruption.
At three hundred fifty thousand years, these hold the record for oldest footprints left by people. If you are a paleontologist, though, you know there's a very big "however," and it has to do with the word "people." Next time.