The University of Queensland (UQ) study is a wakeup call. Mites are usually so small they’re invisible. They break down organic matter for return to the soil, and generally clean up the billions of tons of microscopic waste in the environment. There are 1.25 million species of mites, each with its own niche in places from human skin to anywhere a mite can fit.
If you look at pictures of mites, you’ll see a truly astonishing range of very different looking animals. They can look like spiders, monsters, and strange bugs. The simple fact is that they’re everywhere, usually unseen, and they’re one of the bigger components in the global environment.
Note: I’m no mite expert. I know only the absolute basics. I had to deal with an outbreak of big biting red mites with eucalyptus oil when nothing else would get rid of them, and that’s pretty much it. So when I started to research mite roles in the environment, I was definitely not prepared for the sheer range of roles they have in ecosystems. Looks to me that mite populations are a benchmark for baseline environmental health.
…Which is why their sudden extinction spike is likely to be a real problem. The mites seem to accurately reflect the state of their environments. A healthy environment produces a lot of food for them, and they repay the favor by recycling the waste. So no mites = environmental trouble or an ecological breakdown, on any scale you care to name, micro or macro.
Take this to the level of a drastically increased number of extinctions, and you can see another reason why it’s likely to be big trouble. Mites are extremely tough, made to survive, and they live in demanding environments. They outlived the dinosaurs and the big mass extinctions. They don’t just go extinct because they have nothing better to do. A spike in extinctions is a genuine flashing red light.
Habitat loss, micro level
The main culprit for the extinctions is said to be habitat loss. If you consider what’s likely to be required to actually wipe out a habitat for microscopic animals, it’s an alarming range of possibilities:
• No food: Mites are extremely efficient scavengers on all types of organic matter. No food on this scale means the local environment is their equivalent of an organic desert. If the mite extinctions mean an increase in these dead zones, it’s not good news.
• No return of nutrients to the soil: Billions of mites contribute vast amounts of nutrients to the soil. The mite extinctions could seriously affect croplands and their crop yields. The all-important soil chemistry set requires a lot of nutrients for specific types of plants, too. Mites are major assets to healthy soils. If the mites go, crop yields could go with them.
• Mites are generally the good guys in the human environment: Mites live on mammals, including people. Everyone’s heard of “skin mites” which remove dead skin, for example and very occasionally cause irritations. Dust mites are another common type, sometimes involved in asthma. (My experience with the biting red mites was pretty appalling.) These waste materials the mites eat, however, can become toxic if not removed, and they’re everywhere in every human environment. They’re possible food for fungi and bacteria, too, which can cause significant health issues. While some mites, like ticks, which are gigantic in mite terms, and the notorious scabies mites, can be problems, most of them are pretty useful in human environments.
• Extinctions are instant hits on the affected environments: Extinctions due to habitat loss may or may not result in something else filling the niche. Microfauna, however, tend to form chains of interactions. If one link in the chain goes, the others may go.
More study clearly required
Mites are so diverse that there’s a serious need to understand what these extinctions can do, and how to manage them. Micro environments are complex. The extinctions could also be Silent Spring in another form; an axiomatic symptom of a changing environment which can even destroy these important parts of the ecosystem.
Another way of destroying habitats is the irresponsible use of severe chemical agents, pollution in various forms, and simply creating endless barren wastelands in urban environments. Mites are so hardy they may actually be less affected by climate change, but there’s no guarantee of that, either. There are too many possible causes, in fact, and not enough answers yet. A serious systematic study of what/where/when/how these extinctions happen is definitely needed.
One thing is very clear – Environmental shifts which happen at the bottom of the food chain are always major events. You can rebuild the higher ends of environments, like replacing big things like trees, reintroducing animals into the wild, etc. easily enough.
If the micro-level foundations for the environments go, however, it’s a very different and far more dangerous ballgame. How many mites do you need to support a few million tons per year of wheat or rice, for example? Mite extinctions could be the start of significant environmental breakdowns. We need to know exactly what’s happening, and preferably soon.
