The Burgess Shale is not unique, but for those who study evolution and fossils it has become something of an icon. It provides a reference point and a benchmark, a point of common discussion and an issue of universal scientific interest.

By obtaining a sense of its place in the unfolding drama of life, set in an ecological theatre, so we can understand why it has become one of the leading players.

Evolution is true, it happens, it is the way the world is, and we too are one of its products. This does not mean that evolution does not have metaphysical implications; I remain convinced that this is the case.

The way Conway Morris goes about biting the hand that once fed him would make a shoal of piranha seem decorous.

On a perfect planet such as might be acceptable to a physicist, one might predict that from its origin the diversity of life would grow exponentially until the carrying capacity, however defined, was reached. The fossil record on Earth, however, tells a very different story.

If one compares the sequence of amino acids that go to form the protein haemoglobin, it becomes apparent that humans and chimps are identical and do not differ in a single site.

Scientists don't believe anything.Scientists test things.