From Peter Cochrane, Menstrie, Clackmannanshire, UK
Alan Wilkinson asks whether biologists should have noticed how windscreens were crushing fewer insects by the mid-1960s (Letters, 9 March). I have seen such a decline, but I put it down to aerodynamic improvements in the cars I drive. Has this been taken into account? I am also a motorcyclist and I haven't noticed a fall in the number of insects deposited on my visor or clothing.
