It has been quite a week for those of us interested in the evolution of human beings. On Thursday, David Attenborough gave a talk on BBC radio 4 entitled “The Waterside Ape” and brought us an update on this intriguing theory, first proposed by Prof Alister Hardy in the sixties, and developed and popularized by Elaine Morgan in the seventes and later, a theory which is usually known as “Aquatic Ape” theory of evolution. This suggests that at the time of the split between chimps and humans, early hominids went through a long period of time at the water’s edge, diving and swimming in water, where walking on two legs in shallow water made a very good transition to walking upright. They made a living there from the easy pickings of nutritious sea foods on the beaches and at the bottom of seas and rivers, before returning to the land. It seems that the theory is now known as the “Hardy-Morgan theory of the Waterside Ape” (amongst believers anyway) and Sir David Attenborough gave us a fascinating account of developments in the field in the last 12 years which he thinks support the theory.
Listen to it on http://www.bbc.co.uk/programmes/b07v0hhm ; I think some of the evidence he gives, such as evidence of seafood in sites where ancient hominids have been found, alteration in bones of the ear, which occurs in modern divers, being found in ancient early skeletons of hominids, and others, certainly make it at the very least a very credible theory which should not be dismissed out of hand.
Yet immediately comes back a riposte from physical anthropologists, the scientists who have always been the most scathing about this theory, in the form of Professor Alice Roberts, the well known presenter of programmes on archeology and bone science, who prefers the “Savannah hypothesis”. This is the more masculine theory of man’s origins where we began walking upright as a response to moving on to the savannah, those vast stretches of open grassland, where man is supposed to have adapted to being primarily big game hunters, with the womenfolk taking a more passive role.
She wrote in the “i” newspaper two days later:
“It is a great shame the BBC recently indulged this implausible theory as it distracts from the emerging story of human evolution that is both more complex and more interesting. Because at the end of the day science is about evidence, not wishful thinking,”
Now this is an unduly harsh attack on a theory that has persisted for over 50 years, in which, as is her right, tries to refute the evidence presented by Sir David, (although her brief article is inevitably again short on actual evidence to the contrary), but also chides the BBC for even allowing Sir David, who does know a thing or two about animals, to air his views. He may not be as profoundly a scientist as Alice Roberts in her more specific way, but perhaps he is more of a synthesist. She should be ready to allow that the more discussion on this fascinating dichotomy of views the better for the advancement of scientific knowledge.
Are there any underlying issues here?
I have written several blogs on the topic (see previous articles in my blog), which will give you a background to the difficulties faced all along by the supporters of the Hardy-Morgan theory. At the core of the argument, I believe, is the status of the study of bones in the archeological record as the be all and end all of the scientific endeavour to find the origin of modern human beings. For most of time, bones were all we had, and it is obvious that ancient bones are indeed absolutely crucial to piecing together the history of what actually happened. But inevitably, the evidence from bones omits all the really interesting things happening to the developing hominid body. It will tell you about the stages in the changes in the spine, pelvis, and legs as a result of learning to walk upright, the increase in size of the skull, and the changes in the angle of the skull on the vertebral column, and even about the whereabouts of the hyoid bone – crucial to the ability to speak. But it cannot ever tell you about why and when we lost our hair, why we have a layer of fat bonded with the skin, about our social arrangements, why we sweat as we do, and a myriad of other changes as we developed away from the proto-chimp model. These questions lie outside what bones can tell us, and need the attention of other scientists with a wider outlook; after all it is no coincidence that Prof Hardy the originator of this idea was a marine biologist, not an archeologist. We need thinkers outside the box to come up with further evidence, and these may be other biological scientists, scientists outside biology altogether, and of course non-scientists like Sir David Attenborough and Elaine Morgan. It must be remembered that many advances in the life sciences came from people whose first training was in other areas, and this includes Darwin himself who graduated in theology, and whose initial scientific education was in geology.
Professor Roberts is a professor of Public Engagement in Science at University of Birmingham, and her background is as a medical doctor and anatomist who has specialized in paleopathology. She is of course correct about the huge increase in discoveries of new evidence in Africa of intermediate forms of hominids from different ages, with varying degrees of adaptation to walking erect, the gradual loss of arboreal features such as the opposable big toe, and so on. I readily admit to not knowing much about these new developments, but I agree that some of them seem not really to fit the Waterside Ape theory very well, unless the events of the waterside theory are pushed forward much further forward in time than the original hypothesis of 6-7 mya. But the problem for the archeologists is that they can never be sure of which of these ancient skeletons were actually those of our direct ancestors. There seem to have a great many species of early hominid in Africa at that time, and many of these must have died out, leaving only one to be our immediate forbear. So there are problems with just focusing on the bones. We do in fact need other evidence to add to the story of bones, and I think eventually it is likely to come from DNA. Alice Roberts does not talk much about DNA in any of her books, and like many scientists in the field of paleontology, she would restrict the discussion to bones.
She says herself that the theory of the waterside ape is beguiling; why is that? I think it is fascinating because it chimes with another view of ourselves – not the aggressive savannah ape hunting with tools, but the gentler ape on the seashore, feeding her young in peace on the nutritious seafood which is ideally placed to promote brain growth, intelligence and speech.
Well done the BBC for airing David Attenborough’s talk. I hope that the bone specialists don’t achieve their aim of shutting down discourse on this very important topic. We would all be the poorer if they do. There have been similar responses over climate science and finger print research, and suppression of this sort is the negation of a major principle in science; no-one should have the last word.
Elen Samuel, doctor and writer 
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