Sir — If Ken Weavers wishes to demolish the theory of evolution, fine and dandy; but it really does work better from a position of knowledge (Letters, September 12).

For example, he asks whether there are remains of the many intermediate semi-apes between apes (these are his terms) and humans. Certainly. Many remains have been found of pre-human hominids, for example the various groups of australopithecines and quite a few others.

Weavers' terms suggest that humans evolved from apes, and that is not quite what the theory says: it says that humans and modern apes evolved from some common ancestor. He further claims that the predecessors of modern apes 'apparently developed speech'. Did they? I don't believe that this common ancestor is supposed to have developed speech; this arose in one branch of the subsequently evolved species, not in others. Furthermore, Weavers is saying that 'those that did not [develop speech] remain apes to this day'. But speech is not the only aspect that distinguishes one species of primate from another, let alone one family from another.

Why do modern apes not show signs of developing speech, Weavers asks. Simple: they don't have the anatomical structures that allow speech to take place. These structures could have evolved for all kinds of reasons. Even Neanderthal man didn't have a modern voice box, and the sounds produced by that group would have been very different from those of modern humans, since they would have obeyed the laws of physics.

John Kinory, Steeple Aston