“Big fleas have little fleas
Upon their backs to bite ’em
And little fleas have lesser fleas
And so ad infinitum”
Dean Swift
A few weeks ago our pet hamster called rather confusingly “the mole” died and was sent to his maker in a touching ceremony in the flower bed. I have always liked small animal pets and something that always amazed me with them is how can something so small can have a fully functional, heart, liver, lungs … the lot! Life really does come in all shapes and sizes and we tend to forget that in the great scheme of things we are really REALLY big. Not really a case of the hamster being small but us being, by the standards of the planet very big indeed.
The largest creature that has ever lived on the earth is the blue whale and the biggest of them would be 100 feet long (or tall if you like) this is less than 17 times bigger than a normal adult human , and about the same ratio as me to my late lamented hamster.
Still, even the hamster really wasn’t that small at all when compared with most of the life on earth, microbes, they are small,… really small, but how small?
Sometimes it is hard to think in the measurements scientists use. Most of us know roughly how big a meter or centimetre is, but what about a nanometre?
I prefer to think of things in relation to others (The old football pitch or tennis court measure still helps me get a real feel for certain distances and size). So when trying to scale a microbe I like to think of a dog like a Labrador and call it 1 dog unit in size, ten times smaller than the dog and we get to a mouse, ten times smaller again we get to a fly which is one hundredth of the size of a dog!
Another ten times we get to a tick, ten times smaller again, just on the edge of our vision we get to a dust mite. Ten times again and we get to a red blood cell (which is one hundred thousandth of a dog unit). At a millionth of the size of our truly enormous dog we finally get to a bacteria such as E.coli.
Ten times smaller we get to viruses and I think there we get to the very border of the building blocks of life, because ten times smaller than that (or one hundred millionths of a dog) is a DNA molecule.
After this the Physics boys come in, and we can keep getting smaller and smaller!
Some might say I am obsessed with size… well after all I am a bloke! But seriously the thing that really comes home to me is that microbes are very numerous and can, in some cases be harmful to the bigger stuff, like us (and “the Mole”). This got me thinking, in order to keep the bigger stuff safe and healthy we needed to rethink how we deal with the miniscule stuff. A few years ago some colleagues and I developed an anti-microbial technology which focuses its killing power only on microbes (unlike bleach that indiscriminatingly attacks everything). You could say we picked on the microbes because of their size!
Tags: Byotrol, Hygiene Revolution, microbes, Stephen Falder
