Derrick Holt (Oxford Mail, June 9) says that “we are often known as the ‘fifth ape’”.

He, and other readers, may like to consider one distinctive aspect of human beings compared to other primates – the upright stature of the human body for running, walking and standing.

This involves the following distinctive features: arched feet and a strong big toe, to give stability and to propel the body in motion; fully-extendable hip and knee joints and comparatively long legs; thigh bones which angle inwards from the hips to allow the feet to be kept close together; the slightly s-shaped spine; the spine entering the skull at the bottom rather than at the back, and the flat face for looking forward rather than down during movement; highly-complex inner ear structures for balance.

Each element is an engineering marvel on its own; together, with the necessary skeletal, muscular and nervous infrastructure, they point not to descent with modification, but to an awesome designer.

William Cowan, Grove Street, Oxford