Microbiology is a poorly understood area of science as generally, we cannot see the living things that fall into the category of Microorganisms. The term microbiology seems to produce ideas of an area of the living world that is complicated and high-brow.
Yet is is not complicated or high-brow – it’s just that we need a microscope or just a magnifying glass (lens) to begin to get an idea of what is around us and, in us too. It’s not like looking out into the garden where we can see straight away some of the other living things that share our world.
For children and adults, the easiest thing to do is get a good magnifying glass and some fresh soil (dirt) in a dish. Perhaps add a little water and then look at the soil using the magnifying glass. You may see tiny moving things rushing around in the soil. These are microorganisms: that wasn’t too difficult was it?
More successful though is a cup full of pond water and another dish. Put a little of the pond water in the dish and get that magnifying glass again. Now what do you see?
If you’ve managed to see some tiny creatures rushing around in the water or soil with your magnifying glass, these are large microorganisms! Large because they can be seen with a simple magnifying lens that enlarges things about 5 times. Just imagine what can be seen with a microscope!
The lowest magnification of a microscope is about 10 or perhaps 20 times and it’s quite likely you’ll be able to see 10 or 20 times more than with a magnifying glass.
That is what early scientists did when the first microscopes were invented. This was in the 1600’s – a long time ago. Before then, no-one appeared to know that there was a world within a world and that these tiny living things were so important to us.
With the first microscopes (funny looking things), people who were curious about their world and not at all satisfied with a Church view of things, began to put 2 & 2 together: these tiny living things had an effect on human health.
Although it took a lot of years, scientists (mostly doctors of the day) realised that the organisms in water were linked to disease. Some of the earliest drawings of sewage sludge were made with the use of a microscope and in those drawings were creatures.
Eventually, with more powerful microscopes, the smallest organisms then known were identified and called Bacteria. It was these organisms that were linked mainly to human disease spread via water and the cause of outbreaks of cholera amongst other diseases.
This was just over 100 years ago. The magnification of these microscopes was around 100 times; now we have good magnification up to 1000 times or a little more. Such high magnification needs a little tweaking to allow us to see clearly but, we can see the shape and behaviour of bacteria just as they were when they were alive. (They are killed when we sample and prepare them for seeing under the microscope.
There are no more microorganisms in the world at this time than there were millions of years ago. In fact, there could be less as did you know the enormous chalk and limestone deposits in certain parts of the world, were formed from the bodies of sea microorganisms?
So, perhaps the last comment is confusing? Maybe that’s because bacteria and other microorganisms are usually linked to illness? There a very good microorganisms too – beer is made from the life cycle activities of microorganisms – we wouldn’t want to get rid of those creatures would we?
Even some viruses are OK – they’re not all bad. Viruses are weird things and many biologists think them as non-living because they do nothing until they manage to get into the body of another living thing (not just animals by the way). Viruses are the most recently discovered of microorganisms the reason being they were unseen until Electron Microscopes were invented in the 1930’s.
Doctors and scientists knew they were there for various reasons but had to wait for the invention of a special microscope to confirm their suspicions.
Just like any other microorganism, viruses have been on the planet from the year dot. They are no more around today than they were billions of years ago – it’s just that we are more aware of them and, there’s no virus fossils. That’s why we can’t say viruses were not really around that much all those billions of years ago.
Another way of thinking about it is that where there are living cells around, viruses will also be found as they need another organism’s cell to live in.
The earliest fossils are those of bacteria – not looking like bacteria but like blobs of moulded rock called stromatolites. They can be found in Australia by the ocean. When small bits of these stromatolites are looked at under a microscope, shapes can be seen of ancient bacteria. Their ‘bodies’ were so many that they could form rocks rather like the chalk and limestone but perhaps not in quite such massive amounts.
Perhaps we’ll find the elusive virus fossil eventually; in an insect trapped in a piece of ancient amber? DNA can be found in tiny broken up amounts in amber insects so there’s a good chance a virus will be found soon.
All that and still no direct answer to Why we study Microbiology! Can you pick out, from the article, some ideas as to why we study Microbiology? Give it a go – how many ideas do you have about Why we study Microbiology?
