I’ve been thinking for a very long time that I need to get writing regularly.  Having recently listened to Dr Tim Spector on the radio talking about our microbiome I have been (re)inspired to write about how enmeshed humans are in our environment.  I’m hoping to maintain the mojo for future editions.  My main problem is that I have so much to say that I procrastinate over what to say first, so here goes…


Firstly, I’d like to touch on the concept of an ecosystem.  By training, I am a zoologist so I’ve learned about the complexity of ecosystems and the variety of functions each component plays.  Each part of the system compliments or competes with other components.  An ecosystem tends towards an equilibrium where everything is in balance but various factors can upset that balance.  These are things like differences in availability of food, extreme weather events, and evolution.  The more diverse a system is (biodiversity) the more resilient it is to imbalances.

As an example, let’s look at recent beech ‘mast’ events in New Zealand (2014 and 2016) when climatic conditions have been perfect for a bumper crop of beech seeds.  The beech mast provides lots more food than normal for all who live in the forest, including native birds.  However, the balance tips in favour of the pests such as rats and stoats who experience a population boom as a result of their huge breeding capacity relative to the natives.  This upsets the balance of the ecosystem when the pest species have a greater impact on native birds by eating more eggs and preying on ground dwelling chicks such as kiwi.

Obviously this is a modified ecosystem, like most on earth, and human intervention is an attempt to balance the equation. To help adjust the ecosystem balance back in favour of the birds, the NZ Department of Conservation (DOC) drops 1080 poison.  This has a high success rate but also affects a small number of native birds and dogs can die if they eat a poisoned carcass so it can be controversial.  It’s the best tool in the arsenal at the moment.

The human ecosystem

I thought I had a good idea of how ecosystems worked but never realised how completely entwined we are with the world until more recently.  In particular, I remember an article I saw published some years ago that really made me think about my relationship with the rest of the natural world.  It was by a Norwegian researcher, Fern Wickson, entitled “Why we need to forget about the environment”.

Strong words.  Fern argues we have a problem with the way we are thinking about conserving our planet.  We conserve areas of land or sea thinking the value is in preserving the biodiversity in one area. We have this concept that the environment is something we live in and it’s outside of us. In fact, our bodies harbour more non-human cells than human.  Fern states “Within our bodies, microbial cells outnumber our cells by an astonishing 10-1”.  We are more external environment than human.  And it’s also fairly well known humans are about 60% water.

This struck home.  Our health is fundamentally linked to the health of our microbiome.  Protecting our environment needs to come from a more selfish point of view… we can now argue that we need to protect our environment not because it contains a wonderful variety of plants and animals that provide ecosystem services for us, but because we are the environment and the changes we are making to the environment affect our very being, our own personal ecosystem.

The microbiome

I’ve been interested in the bugs and bacteria that are a part of us ever since I read Fern’s article.  Last week my newsletter featured a radio interview with Dr Spector, a Clinical Epidemiologist, who has been studying our microbiome for decades.

It’s fascinating.  Every person has a unique biome. All mammals are basically born sterile, without any microbes of their own and they are “seeded” as they pass down the vaginal canal by their mother’s microbes, microbes that are there specifically for this purpose.  This is an essential start and helps populate the gut from the first breath of air to allow the baby to digest breast milk.  Wow.

Our microbiome is on our skin, in our gut, our blood, our bones, it is everywhere.  We are literally a living, breathing ecosystem and our ecosystem equilibrium can easily be upset by environmental changes like changes in diet, exposure to pollution, not getting enough fibre or particular nutrients, taking antibiotics, which, as the name suggests, are anti-microbial, indiscriminately targeting good and bad bacteria.


In order to maintain a healthy personal colony of bugs, we depend on resources from outside our body.  Nutrients.  This means our food systems are important.  Whole foods with real nutrients are important.  Fresh local food, where the plants are as fresh as possible when they arrive to you (and have less carbon emissions from transport), are important.  And it follows that soil is important to grow food that is nutritious.

Dr Spector tells us we’ve lost about a third of our microbiome in the last few decades and this is directly related to diet.  Hunter gatherers ate about 500 types of plant and animal by season, now we eat in a modern diet about 40 types of foods.

Modern agricultural practices are often intensive and performed as a monoculture (one species) with little or no biodiversity.  We need to use pesticides to keep pests away, herbicides to keep weeds away, antibiotics to stop the spread of disease in close quarters, and chemical fertilisers to make plants grow because the soil is not being naturally replenished with nutrients.

We need diversity in order to be healthy.  The old adage “everything in moderation” is a pretty good one.

Ecosystem services

So we come full circle back to the ecosystem and the benefits of biodiversity to a resilient system.  When an ecosystem is healthy, it provides ecosystem services that benefit humans, such as breaking down waste and building soil, purifying water, capturing carbon and producing oxygen.
What’s more, we don’t need to pay for this service.  A healthy ecosystem functions without the human invention of money.  But it certainly does have enormous value and should be factored into our finances because humans value money.

An example of an ecosystem service with a twist comes from another featured article last week.  It talks about “goodies versus baddies” on a farm and how the classification of friend or foe isn’t as clear cut as we might imagine.

The example given is of cockatoos in almond orchards.  They are classified a pest because they love to eat the almonds.  Farmers chase them away.  But when the almond tree has finished fruiting, unripened seeds remain that can to rot on the trees and cause disease.  The farmer employs workers to take them off the tree.  The cockatoos, if they weren’t chased away, do that for free.  Their clean up service is better value for money than paying humans to do it and better for the environment too.  It’s worth losing a few good nuts to have all the bad nuts cleaned up later.

The real value in caring for our planet is that it benefits each one of us directly through the health of our microbiome.  If we nurture healthy ecosystems, we nurture ourselves.  We need to recognise the importance and value of a healthy planet, not just the rainforest in the Amazon or the Great Barrier Reef, but everywhere: our bodies, our farming, our mining and energy, and our cities. That means encouraging biodiversity.

Nature doesn’t need people. People need nature.

Concepts arising in this blog post to think about:

  • Complexity and diversity in the environment are important
  • Human intervention in ecosystem balance
  • We’re more non-human than human
  • Water is a vital resource so water quality is vitally important
  • Soil health, plant health and food health go hand in hand
  • Biodiversity loss outside of forests, in agriculture and the built environment
  • Impact of agricultural systems
  • Antibiotic overuse in farming and resistance
  • Ecosystems perform vital services that can be calculated in monetary terms
  • Be open to thinking of the role of flora and fauna from different perspectives

What interests you?  Help me with my procrastination problems and let me know what you would like to learn more about.

Categories: Blog


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