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Which end of the food chain are you?


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Which End of the Food Chain are You?

 

I remember first hearing about the food chain in a school biology lesson. There was a neat little picture of a grasshopper eating a plant, a small bird about to pounce on the grasshopper and an eagle hovering menacingly above the small bird, the four of them linked by big, black, sweeping arrows to show just who was eating whom.

 

Nowadays one can rarely watch a nature documentary without hearing a reference to the food chain and the way the food chains interconnect to form an ecosystem. The general impression we get is that the most successful animal in an ecosystem is the one at the top of the food chain, the one that has no predators and that everything else is just there to feed him.

 

With a population now in excess of six billion and with no predators we assume that we are the most successful life form on the planet. But this overlooks one small point, or to be more accurate several billion billion small points. There are two types of life that have been around since before the dinosaurs were a mere twinkle in the eye of evolution that make our achievements look positively anaemic. These are bacteria and viruses.

 

Two of the reasons for our success as a species are our ability to eat a wide variety of plant and animal life and our adaptability. Bacteria and viruses can live virtually anywhere and prey on every living thing including us. We don’t even come a close second. Bacteria in particular are the biochemical power house of the planet, the recycling system par excellence and without them we couldn’t live. Paradoxically they are also our biggest killer.

 

The reason they don’t wipe us out all together can be summed up in one word: biodiversity. Envisage a simple ecosystem with 100 different types of animal and plant and 10 types of potentially lethal bacteria and virus. Every plant and animal has a one in ten chance of contracting something deadly. Of those that do, maybe one in a thousand individuals have a natural immunity. The species doesn’t die out but is left with a tiny remnant with which to re-establish itself. Sometimes they do, sometimes they don’t; this is natural extinction.

 

But what would happen if your ecosystem only contained 10 different types of animal and plant? Statistically, every species would be hit and everything would be virtually wiped out. In practice, some species would come through unharmed whilst others would be fighting off two or three different pathogens simultaneously and the number of individuals with natural immunity to all three would not be enough for the species to survive. This theoretical ecosystem would then be reduced to only five species of animal and plant, each with double the chance of contracting something deadly. Multiply this little theoretical ecosystem up to cover life on Earth as it is now and worrying things start to become obvious.

 

The whole process comes to a shuddering halt in what is known as a Mass Extinction Event where complex life on Earth is reduced to virtually zero and evolution has to begin again. This has happened many times before and will surely happen repeatedly in the future. Meteor strikes and sudden climate change have tilted the balance in the past. The cold, dispassionate and virtually total eradication of all the complex life forms on the planet.

 

This time it’s personal. We are creating our own Mass Extinction Event.

 

If you get the chance to read Bill Bryson’s excellent book “A Short History Of Nearly Everything” you will come across the following passage on page 566: “According to the University of Chicago palaeontologist David Raup, the background rate of extinction on Earth throughout biological history has been one species lost every four years on average. According to Richard Leakey and Roger Lewin in The Sixth Extinction human-caused extinction now may be running at as much as 120,000 times that level.”

 

This does not affect bacteria and viruses in any way. They merely mutate and prey on what is left. We are systematically cleansing the planet of everything that is not of immediate value to us. We all know about the wholesale destruction of the rainforests to make way for agricultural and pasture land. We all know about the illegal logging of vital hardwoods for the sake of profit. We all know that species become endangered and then lost for ever as man’s ever increasing numbers encroach on their habitats.

 

We all agree that these are terrible things. But how many of us have worked it through to its logical conclusion: the fewer the number of animal and plant species the greater the chance of our livestock, our crops and even ourselves being hit by simultaneous viral and or bacteriological infections?

 

This is not something that may happen in the dim and distant future this is something that could be on next month’s news broadcasts: “The State of California has declared a state-of-emergency. California, which has the highest proportion of people infected with the HIV virus in the United States has been dealt a double blow with the outbreak of M1BF - mutation one bird flu. Thousands are dying daily as M1BF, though to have been brought in by an airline passenger flying in from…”

 

The question arises, what can we do to reverse this trend? There are two things:

Keep as many species alive as possible even if this means taking them out of their threatened habitats and breeding them in captivity. A sort of modern day Noah’s Ark, until businesses and governments wake up to the fact that there’s something far more important than the bottom line and fiscal policy. Hint: it’s what you do with the profit that counts guys.

Hope and pray that 1) is not too little too late.

 

Here at Little Lemur Publishing we are trying to do just that. We have always allocated 5% of our turnover to organisations involved in the captive breeding and or habitat protection of five endangered species, namely the Ruffed Lemur of Madagascar, the Wolverine in the far northern hemisphere, the Iberian Lynx, the ‘European’ Brown Bear and the Mediterranean Monk Seal. Not particularly high profile species but as we have seen every remaining animal and plant is vital to our own preservation. We have decided that 5% is not enough. All of our profits now go to help preserve these five species, not a penny is taken out in salaries or administration. With your help we can increase the number of species we help and the amount of help we can give them.

 

Please visit us at http://www.littlelemur.com where you will find a host of books that can be emailed to your computer at a fraction of the price of printed books (no paper = no trees felled). If you’ve never tried reading a novel on-screen before then I urge you to give it a try. In doing so you’ll be doing one small thing towards the preservation of life on Earth as we know it and if we all do one small thing the cumulative effects could make all the difference.

 

Steve Daniels, Ierapetra, Crete, Greece 9.October 2006

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