Watch and savor this remarkable video by Daniel Stoupin. It shows tiny marine animals in motion — motions that are typically so slow that we would never notice, here enormously sped-up so that humans can appreciate them.
I found it at this blog post by Peter Godfrey-Smith, a philosopher of biology. He notes that some kinds of basic processes, like breathing, are likely common to creatures that live at all different timescales; but others, like reaching out and grasping things, might not be open to creatures in the slow domain. Which raises the question: what kinds of motion are available to slow life that we fast-movers can’t experience?
Not all timescales are created equal. In the real world, the size of atoms sets a fundamental length, and chemical reactions set fundamental times, out of which everything larger is composed. We will never find a naturally-occurring life form, here on Earth or elsewhere in the universe, whose heart beats once per zeptosecond. But who knows? Maybe there are beings whose “hearts” beat once per millennium.