Thursday, June 30, 2011

Ruminations

My current preoccupation with evolution makes me feel a bit like Don Quixote tilting at windmills: the egregious eccentric fretting about debates on the unknowable.

So far as ecology is concerned David Deutsch (2011) summed up one of my own feelings when he wrote “if you fill a kettle with water and switch it on, all the supercomputers on Earth working for the age of the universe could not solve the equations that predict what all those water molecules will do – even if we could somehow determine their initial state and that of all the outside influences on them, which is itself an intractable task.” Substitute the molecules in Emthree for those in the kettle and the task becomes even more intractable.  I cannot predict what Emthree will do.  And even if I knew all the biological and physical variables, I cannot predict what I will do.

I also liked Gordon Rattray Taylor’s remark in 1983: “within one square metre of ground, a score of species of snail may be found. What advantage can any one of them have?” (Emthree has so far produced 15 species of mollusc, but I expect it would have been 20 if it was on calcareous soil).

Maybe each species of snail evolved long ago when there was significant competition with a neighbouring species, but once one had died out, the survivor could live with less closely related relatives because they were not directly competing. Explanations can, of course, be thought up for anything, but they are not necessarily correct.

Wednesday, June 01, 2011

Dry June arrives

After a cold winter, a long drought is now causing serious concern among the farming community in South East England. Today it was warm, but for the last week or two it has been dry, cold and windy with only a few inconsequential showers.

Emthree is really only just beginning to show the effects of the weather. The grass is bright green, but rather sparse, with a dead, dry layer on the ground. In the midday heat many of the larger plants wilt.

There are a good few flowers: creeping buttercup, narrow-leaved vetch, smooth hawksbeard, still a few forget-me-nots, herb robert, cinquefoil and heath speedwell that has now spread far and wide. There is sweet vernal grass and rough meadow grass, the first going over, the second just beginning. A gladdon iris is flowering in Medlar Wood and so is the plant of herb bennett, a first for the project area.

The leaves of the smaller birch are heavily mined by the fly Agromyza alnibetulae (ostensibly a first for Sussex, but I expect it is not uncommon) and there are great colonies of purple aphids, Uroleucon jaceae, on several of the black knapweed stems.

20110601 Emthree Houseleeks 010