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Health, Sports & Psychology
  • Audio
  • 10 mins
  • Level 1: Introductory

The secret ingredients

Updated Monday 13th September 2010

The Saving Species team is joined by paediatrician and diversity of nature advocate Aaron Bernstein, as they take a slice of the pie of life and explore the hidden treasures of the interdependent system that is biodiversity.



Copyright open university


Presenter:  It’s a rather lovely sultry kind of June day looking out over a major reservoir that feeds the city of Bristol.  A few yachts sailing peacefully by, some ducks quacking, and surrounding us are lots of hills, fields, agricultural land and forests.  I see a lovely lake, opportunity for some relaxation and some sport, and welcome fresh water for our city, is that what you see?

Aaron Bernstein:  I do.  It’s a pretty lovely spot we’ve got here.  We’re sitting in the middle of a watershed that is a major sponge that purifies the city’s water, just like similar ecosystems all over the world purify the water for hundreds of millions of city dwellers.

Presenter:  When you say purify the water, can you tell me what you mean by that?

Aaron Bernstein:  Sure.  There is an abundance of microbial life that can actually break down chemicals that would enter into the water supply, and these include everything from agricultural chemicals to industrial chemicals, and what’s remarkable about these microbes is that they do this of course for free, whereas human constructed water filtration plants generally do nothing to remove these toxic substances from water.

Presenter:  We can put people on the moon.  We can do all kinds of things.

Aaron Bernstein:  Absolutely, we could remove those toxics if we really wanted to with some sort of filtration process, but of course that requires building the infrastructure and paying for it.  But these microbes – we don’t pay anything.  In fact we know precious little about the microbes that live on this planet, even though it’s quite clear that they are at least, at a genetic level, the most diverse creatures around.  There’s more diversity in the genomes of the microbial life forms on earth than in all of the things we can see.

Presenter:  So bringing us back to this lake in front of us, if I’m going to talk about the biodiversity that’s around this lake, I will obviously talk about these lovely spring flowers that are everywhere, we can hear some birds singing, there’s ducks and swans, but that in effect then is only the tip of the iceberg?

Aaron Bernstein:  That’s right.  So many of us were taught that there are five kingdoms of life, so that there are the animals, the plants, the fungi, the so called protists and the monera, and the five kingdoms are very colourful.  A nice way of thinking about life, but they don’t do biodiversity justice because they don’t really divide the pie of life up equally.  It comes as a bit of jarring news to people that in fact there may be more microbes in us and on us than there are cells of us.  

Presenter:  Do you think we’re on the wrong track then? Do you think that when we talk a lot in the conservation world about preserving biodiversity because the more biodiversity we have the healthier the ecosystems of the world, that in a sense our focus is in the wrong place and that we ought to be looking in a different area; we ought to be looking to the microbial world much more than we are the big mega fauna like the polar bears and the lions?

Aaron Bernstein:  I think that the focus is well placed because it’s much easier for someone to form an emotional attachment to a penguin or a polar bear or a colourful bird than it is with the microbial life that clearly has relevance to our wellbeing.  We need to above all motivate people to be interested in nature in a way that is tremendously important to conserving it.  At the same time, and this is the International Year of Biodiversity, I think it is critical that we rethink this idea of biodiversity.

Because right now I think people when they hear this word they think about big charismatic creatures, which are just a very small part of what this term really means.  And one way to broaden that definition is to understand that all of that life depends upon creatures we can’t see.  And this transforms the understanding of our natural surroundings.  Such that if you’re going to protect, for example, a tropical rainforest or this watershed, saving all the individual tree species is missing the point.  You need to protect the habitat. You need to protect the ecosystem.  And only when you protect the ecosystem will you provide the resources both for humans and for the rest of the creatures.

Presenter:  But by preserving say that beautiful oak tree sitting in that field over there, and I say no I really want to protect that, I don’t want it to be chopped down, am I also not then protecting lots and lots of other things seen and unseen as well?

Aaron Bernstein:  That’s right, we must, if we’re to do what’s necessary to stave off the current extinction event, we have to garner a broader understanding not only that biodiversity is more than a list of species, but that it is an entirely interdependent system.  And without that understanding it’s going to be very hard to conserve the essential services, such as providing, as this watershed provides, for both this generation and future generations.

Presenter:  And those darker moments when you consider the state that we’re in at the moment, and when I say ‘we’ I mean the whole of the earth really, the environmental problems that seem to be so huge.  Could you put your finger on one and say that’s the one that keeps me awake at night?

Aaron Bernstein:  People tend to think when I speak that I must be the world’s greatest pessimist.  I actually am quite an optimist, and here’s why.  We know almost nothing about nature, even in this year 2010, and we’re doing a tremendous amount right now to uncover the diversity of life in a way that’s never been done, on a scale that’s never been done, and it’s tremendously exciting because every day we learn so much more about this extraordinary diversity of life.  And one of the things I've learned as a paediatrician that is particularly relevant to conservation is that if you’re going to change people’s behaviour you can’t expect them to change what they do without understanding what’s at stake for themselves.

So if I tell a family that their child needs to lose weight, without giving them some understanding of what the consequences for that child’s health are, I can’t expect them to do that unless they understand what’s at stake for the child’s wellbeing.  And the same holds true for the issue of motivating people to do what’s necessary to conserve biological diversity.  For 40 years people have made very compelling and extremely articulate arguments to protect nature because, for example, species have a right to exist on their own, or because it is unethical to harm nature.  And yet here we are in 2010 with rates of extinctions as high as they’ve ever been since humans have walked the planet.  And so we have to ask ourselves why that’s the case.

And I think one of the reasons is because we have not done a very good job of making it clear to people what is at stake for their wellbeing.  And from my perspective human health depends on biodiversity in every conceivable way, not just for the food we eat, although clearly we would be lost without diversity in our agricultural base, or for the water that we drink, as is so evident here sitting on this gorgeous watershed, but also for the medicines we take.  And so I think we need to do a better job of informing people that what is at stake with the loss of biological diversity is not just the opportunity to witness unique creatures, but it is fundamentally an issue of our health.

Spiderweb with morning dew Copyrighted image Icon Copyright: Jacek Chabraszewski |

Spiderweb with morning dew


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