Seed head

What did the economist say to the ecologist?

At this meeting we got a chance to find out. Organised by a group of forward-thinking ecologists and economists and held at LSE, Eco**2 was an opportunity to find out what the ‘other side’ looked like. Prior to this meeting many of the participants had no idea and it was quite a revelation to find out how similar the two disciplines are, although they appear to deal with entirely different systems.


In some ways we face the same problem: how to understand a complex dynamic system, where the elements interact and the elements themselves exhibit complex behaviour. Both disciplines use models to make useful predictions: people in the real world want to know the future state of the economy and increasingly ecologists are being asked to predict the likely future state of ecological systems, such as the occurrence and severity of toxic ‘red tides’. This ‘forecasting’ was much discussed at the meeting: do we really have adequate models for this purpose? How can we convey uncertainty in our predictions and more importantly the consequences of that uncertainty. If we’re wrong will it cost millions or billions? Will it lead to a few less fish or the collapse of an entire stock? And how can we factor in the dreaded ‘unknown unknowns’? Indeed Alan Kirman reminded us that the Queen had actually written to the British Academy asking why the financial crisis of 2008 was not foreseen. Their reply should strike fear into the heart of anyone who starts to have too much faith in their models: So in summary, Your Majesty, the failure to foresee the timing, extent and severity of the crisis and to head it off, while it had many causes, was principally a failure of the collective imagination of many bright people, both in this country and internationally, to understand the risks to the system as a whole.

Lessons for ecologists

A heartening aspect of the programme was the interest showed by many economists in the natural world and their obvious concern that resource limitation and biodiversity loss were simply not being factored into economic models. In particular it was refreshing to hear Partha Dasgupta, an eminent economist, making an impassioned plea NOT to start pricing every species or to believe that you can’t fight for nature unless you can prove unequivocally that it has some substantial monetary value. Indeed, he suggested that this is a dangerous idea – the lack of ownership makes the natural world peculiarly vulnerable – and we need to learn to value it for its own sake. Ultimately, after all, we know that we depend on it. Let’s not forget that in 2008 failure to understand the risks to the system as a whole lulled otherwise smart economists into thinking that tomorrow would be much like today. I’m pretty sure we have no idea how many species we can ‘safely’ lose without posing a substantial risk to the Earth’s life-support system; nor could this damage be reversed. So fighting for every one seems like a pretty good idea.


An interesting debate emerged about equilibria in both economic and ecological models. George Sugihara wants us to abandon them and embrace the idea that many ecological systems are inherently non-linear and switch between alternate states. He provided a clear exposition of his 2012 Science paper where he reminded us that if two variables aren’t correlated, it doesn’t mean they aren’t causally linked. This reversal of the well-known maxim that correlation is not causation is highly non-intuitive. But his method might indeed lead to better forecasting, especially in marine systems where such non-linearities are almost certainly widespread and the current models hopelessly inadequate. Worse, despite their poor predictive power and simplistic assumptions, these models are currently mandatory in the management of US fish stocks. Again a frightening reminder that today’s idle academic exercise could be tomorrow’s financial crisis.

The future

In the final session we reviewed what we’d learned and asked: would we do it again? There seemed to be a general feeling that we would – but now that the initial pleasantries are over, we need to get down to business. Three options were suggested: 1) how to include economic thinking in ecological models; 2) how to include ecological thinking in economic models and 3) how to move forward with a genuine ‘ecological economics’. Let’s hope that at least some of the participants make the time to do so. It was pretty clear that there’s plenty of work to be done.