How blackcurrants grow

When blackcurrant leaves appear at the end of the shoot, they at first appear to be in opposite pairs. As the shoot continues to grow the spaces between the leaf-stalks elongate dramatically, and they are then seen to be alternate. If you imagine that you are looking down the stalk from the shoot, each leaf is rotated clockwise from the previous one by an an angle that averages 160 degrees. Hence, the stalk of leaf 10 lies directly above the stalk of leaf 1 (9 * 160 = 1440 = 4 * 360). At least, that's how I think it works. Anyway, it isn't simple.

My review of the heyday of the English progressive rock band Van Der Graaf Generator is now online in Stride Magazine. It's also in its appropriate place (1971) in the "Brief History of Western Culture" - see the links over there on the right.