Well, Mr Red, had you written that in an 'A' Level essay you'd have had a big red line scrawled through it. For all the world you seemed to be saying that there were no fungi around at that time. I wasn't selective in quoting your sentence. Still, point taken. But do study that article. The supposed ineptitude of Carboniferous fungi may not have been to blame for our abundant coal seams after all.

I should also like to point out to you that not "all" coal reserves were laid down at the time in question. There are considerable coal deposits of tertiary (post-Cretaceous) age in the US, India, south-east Asia, Ireland and elsewhere, all with economic potential. Indeed, in a clay pit a few miles from me there are coal seams of tertiary age. These were even exploited on a small scale at one time. The Carboniferous represented a peak, not the whole.

It's not only a finite resource, Raedwulf, it's the source, along with oil and gas, of the unlocked carbon that is rapidly increasing CO2 concentration in the atmosphere. What is unsustainable is the rate at which we are unlocking the carbon (which far outstrips the rate of renewal), not because we'll run out of fossil fuel but because of the effect on climate, not to speak of the toxic nature of pollutants associated with fossil fuel burning.

A peat bed may have taken ten or twelve thousand years to grow a few metres thick. If that peat is stripped to the bedrock in a hundred years, it will have been removed a hundred times faster than its rate of renewal - even if the conditions are still right for its renewal. Which climate change may dictate that they're not. We're in trouble, aren't we? I suppose we could "get round it" by pledging to take just a hundredth of all the peat each hundred years. Not how it goes, though, is it?