Footprints

The first image is of the Laetoli footprint found in Tanzania, where one of our hominid ancestors walked through muddy sand 3.6 million years ago.
The second image probably needs no explanation - it's Neil Armstrong's footprint on the moon, left there 3.6 million years later.

How many generations between then and now. How many people born, lived, loved, hoped, dreamed. How many still to come.

We've come a long way, haven't we.