Deep Time: Cladistics, The Revolution in Evolution (Paperback)

If, as Henry Gee states, most professional palaeontologists "rejected the story-telling mode of evolutionary history as unscientific more than 30 years ago', then the appearance of a book about cladistics - the subject of "Deep Time" - is long overdue. Cladistics is the science of relationships based on verifiable attributes, as gleaned from comparative anatomy, physiology and embryology, from palaeontology and recently also from the comparison of gene sequences in plants and animals.

Such studies, in the view of cladists such as Gee, lead only to patterns of kinship - degrees of closeness of relationship based on observable features of structure and form. Any interpretation or extrapolation of such data to generate evolutionary lineages - lines of descent - is unscientific and therefore invalid. Such narratives of human or animal evolution are just that - stories invented to satisfy subjective prejudices about our place in nature, in particular about the presumed inevitable upward progression of evolution. "Deep Time", the 4.5 billion-year history of the Earth, and the extraordinary sparsity of the fossil record allow no valid conclusions to be drawn about how or why evolution occurred.

Cladistics claims to be an objective scientific method primarily on the basis that it is testable. Yet Gee admits that the test applied by cladists - Occam's Razor or the Principle of Parsimony - is unreliable and can never reveal the truth, which Gee says is unknowable. We are therefore left hanging in the void. We are told that 'almost everything we have been told about evolution is wrong', that we must abandon the stories of a progressive evolutionary process leading to Man, but we are given instead a scientific method which has nothing to say about the 'how' or 'why' of evolution and which is in any case apparently unreliable.

There is a further paradox. If the objective facts studied by cladists can say nothing about the how or why, then they can neither confirm nor deny Darwin's theory. Gee seems strangely ambivalent about this, at times acceping the lack of proof for Darwinism, at others using the assumption of the fact of natural selection to make his case e.g. when he simply asserts that evolution (because it is Darwinian) can have no direction or purpose.

Cladistics should nonetheless be welcomed. It has potential - if objectively pursued - to cut through the pseudo-science which currently bedevils evolution theory. It can help us towards a clearer view of our place in nature - but only if it is genuinely open to ALL the facts.

There is a kind of sub-plot to "Deep Time", in which Gee joins those who feel the need to knock humans off any kind of imagined pedestal, to reduce us to an insignificant accident of cosmic history. Bipedality, the manufacture and use of tools, language, intelligence, creativity and self-consciousness are all dismised as 'really not very special'. One has to ask if this is an objective assessment of the facts, unprejudiced by personal preferences and why it is that Gee fails to mention those facts of comparative embryology and anatomy which tell a very different story of evolution from the Darwinian one.