Small creatures – big impact
This first blog of 2025 introduces us to a new theme for the year: ‘From micro to macro,’ where we will be delving into, celebrating and sharing together the diverse and complex world we live in. We will highlight the extraordinary, grapple theologically and bring to the fore work of A Rocha projects from around the globe. We kick off with the micro and the smallest microorganisms and creatures in our ecosystems and biome.
I have a science and journalist background and so was curious about what a microorganism technically is, and what roles they play in our world. It turns out to be a catch all for any living thing that can’t be seen with the naked eye. Microorganisms are viruses, bacteria, archaea, (similar to bacteria and live in extreme environments) fungi and protists (neither animal or plant, single cell organisms like algae) Although they weren’t discovered until 360 years ago, humans were aware of diseases that affected them as well as animals and crops, and measures were put into place to guard against them. Certainly in historic writings, the possible existence of microscopic organisms were discussed by Jains in India in the sixth century.
A Roman scholar named Marcus Terentius Varroin in the first-century BC wrote a book where he called the unseen creatures animalia minuta, and warns against locating a homestead near a swamp:
‘… and because there are bred certain minute creatures that cannot be seen by the eyes, which float in the air and enter the body through the mouth and nose and they cause serious diseases.’
And of course, we can see the work of microbes through the Bible, for food stuffs – bread, cheese and beer and diseases, boils, plagues, dysentery. And why was ceremonial washing so important in the Law of Moses? The Law was built around control of infection and public health principles that we continue to hold today. The existence of microbes was discovered by a Dutch draper called Antonie van Leeuwenhoek whose hobby was creating lenses for microscopes where he discovered bacteria and protozoans, tiny creatures he called animalcules. His discoveries were seen as insignificant and ‘oddities of nature’. It was 200 years later in 1850 when Louis Pasteur found that microorganisms caused food spoilage and that bacteria could rapidly multiply, that the science of microbiology was established.
We now know that our planet is populated by at least a trillion species of microorganisms and thankfully only about 1400 species cause infectious diseases. A whole library could be written on the importance, influence and incredible facts about microorganisms but here are a few I share with you.
The human body contains trillions of microorganisms, outnumbering human cells by 10 to 1 but only making up 3% of our body mass as they are so tiny. We forget that bacteria not only cause infectious disease but for the majority the natural state is symbiosis – a mutual benefit between host and microorganism.
We can’t be completely sure, but most scientists concur that microorganisms existed around 3.9 billion years ago and have permeated every ecosystem and space throughout the planet. A class called extremophiles, are microbes living in the most hostile environments. Thermophiles thriving in compost heaps and hydrothermal vents heated by magma, bacteria under enormous pressure on the sea floor, our own microbiota at low pH in the stomach, heavy-metal-adapted strains in mines and fungi surviving extreme radiation in Chernobyl.
We humans live in a symbiotic relationship with microorganisms both individually (think of your gut) and collectively. These invisible organisms are the powerhouse of circulating and distributing nutrients and chemicals like water, oxygen and carbon dioxide around our planet.
Without microbial decomposer communities, life would be smothered in dead organisms. They carry out on land and in water almost half of the photosynthesis on our planet, increasing oxygen levels and lowering carbon dioxide. The Bible understandably doesn’t mention these invisible work horses, but again their presence influenced human behaviour and created societal customs and laws built up over centuries. Some of the plagues in Exodus, where Moses was trying to persuade the Pharoah to free the Israelites could have been unusual incidences of microorganism activity. Perhaps a dinoflagallate bloom could have turned the River Nile red (Plague 1), driven the toads away to look for food (Plague 2) and even caused the deaths of the firstborn (Plague 10). It is interesting to speculate that this may have been as a result of mycotoxins produced by fungi (e.g. Stachybotrys species) on grain stored hurriedly and badly to get it away from the storm and locusts; the firstborn of each family would get a double portion at the meal table, and therefore tip over into the lethal dose of the mycotoxins!
As with much of science, the more we investigate, measure and experiment, the more questions we unearth and so scientific research continues. A Rocha is also part of those scientific studies, and two national organisations are researching on the microorganism level.
Both A Rocha Ghana and A Rocha Canada run water quality monitoring programmes. In A Rocha Canada, their water quality project includes working with the Semiahmoo First Nation whose traditional shellfishery closed due to water contamination due to pollutants and bacterial strains. A Rocha’s work is to assess water quality in order to identify sources of pollution and advocate for their cleanup. They provide this data to the relevant authorities as evidence of progress of the clean-up efforts. The aim is for the watershed to once again be healthy enough to support a viable shellfishery.
What is less researched is the far greater picture of what affect climate change will have on microorganisms – the ‘unseen majority’. Microorganisms support the existence of all higher life forms. They are indeed the building blocks to all life. Microorganisms will affect climate change (including production and consumption of greenhouse gases) but are also affected by climate change.
How the human species will survive in the far future we cannot know, but we can certainly be sure that microorganisms will survive with us. In this verse Paul was writing to the Corinthians about spiritual matters and forgive me for maybe stretching this too far but perhaps it could be applied to the ‘unseen majority’ that live symbiotically with us.
‘So we fix our eyes not on what is seen, but on what is unseen, since what is seen is
temporary, but what is unseen is eternal.’ 2 Corinthians 4:18 (NIV)
By Debbie Wright
You may also be interested in:
