As I write this I realise that I learnt biology before DNA was known and I don't know enough to answer this question*.

Highgate Pond 3. A beautiful evening of sunlight and shadow. I'm sitting by the water. This part of the heath is more a park than a forest - there are isolated trees growing in mowed grass on which people are sitting in small groups and picnics. Their voices carry across the water.

I came here this evening by following the second hand of my watch at each junction of pathways (I usually decide to walk in the wilder parts). So now I am among things I didn't choose to visit. Perhaps soon I will discover something that, without a chance process, I'd not have encountered.

Now I am standing by a patch of creeping thistle, about 100 by 50 metres. There is a notice board in which it is described as an invasive species. They are going to mow certain fields to prevent it becoming dominant - as it has in this patch where most of the grass has already gone. (See entry on 14 may 2004 about a patch of thistle and a footnote on 1 july 2004 on invasive species)... Is this what the chance process is teaching me this evening? Or did I know it already?

(these pages are designed to be read with the window set to two-thirds of the screen width)