Survivors: The Animals and Plants that Time has Left Behind - Richard Fortey

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a few fluffy white clouds in a faultlessly blue sky. My companions are astonished, it was the best day they had seen in the last decade. The warden of the Reserve came from Wales, and remarked ruefully that he had chosen to work in the only place in the world with worse weather than Ffestiniog. One of the Newfoundlanders mumbles to me under his breath that the warden will be betrothed before Christmas. ‘Not a lot of single men around here’, he says, with a wink.

      At Mistaken Point, a path leads for a mile across a bleak coastal heath, which is less forbidding examined closely. Berry-bearing plants hidden in the close sward bear blue-black or scarlet fruits, and bright yellow tormentil flowers smile at us along the way. Patches of Sphagnum bog support pitcher plants whose leaves trap flies and mosquitoes to compensate for the poor nutrition offered by the damp wilderness. Even wild roses are tucked into natural hollows. As we approach the sea, grasses take over to make a natural lawn. Fulmars wheel in and out, just to have a look. The path leads onto the cliffs, which are quite comfortable to clamber over in this part of the Avalon Peninsula. The sedimentary rocks of which they are composed form a series of ledges that dip at a gentle angle into the sea, forming steps that we can climb up or down to explore different strata. The rocks are dark in colour, and the more resistant beds have made natural groynes that project out into the ocean. Waves break continuously over the ledges, throwing up foam – and this on a calm day. When winter storms are raging, salt spray must blast all the exposed surfaces. It is not hard to imagine how Mistaken Point got its name. The bones of fifty ships lie offshore, waiting to be fossilised.

      Each of the flat surfaces exposed on the ledges is an ancient sea floor. In 1967, a graduate student geologist called S. B. Misra at Memorial University of Newfoundland discovered the most extraordinary organic remains preserved on these stretches of petrified sediment surfaces. Only a year later an account of the finds had been published in the most prestigious scientific journal Nature, jointly with Mike Anderson, also of Memorial University. The rocks were recognised as being late Precambrian in age (this was long before the Ediacaran had been named). There was palpable excitement in the scientific community at finding such large fossils in rocks of this great antiquity, although it was not known at the time just how old they were. Misra subsequently described the original conditions under which the sediments had been deposited. There were some special features about this discovery. First, the fossils could not be safely collected. They were impressions on the exposed surfaces of a very hard but brittle rock, shot through with cracks, and often located in the middle of a great uncompromising slab. The best way to study the remains was to pour a latex solution onto the surface of the rock, allow it to dry – even that might be a challenge with the Atlantic hard by and fog always lurking in damp banks – and then take the hardened cast off to somewhere nice and warm. For scientific description it is usual to have an actual specimen on which to found a scientific name, and this should be kept in perpetuity in a public museum. This was obviously going to pose a problem, unless a public museum was constructed over the cliffs. Second, with such unusual material it is rather hard to know where to begin, since most of the usual biological pointers are absent. How does one describe an enigma, except as ‘enigmatic’? Perhaps it was a combination of these factors that stalled a full account of these remarkable fossils. Anderson took over the material when Misra went back to India, and when I met him in the late 1970s he seemed to be crippled into inaction by these admittedly difficult problems. At the same time, he put his marker down upon the fossils so that nobody else could study them. The result was that most of the Mistaken Point fossils did not receive proper descriptions and the respectability of scientific names for several decades. Guy Narbonne and his colleagues from Queen’s University, Ontario, are making good this omission even now. It is a strange fact about science that until an object or a phenomenon receives a name in some way it does not exist. Names really matter. They retrieve something from an endless chaos of anonymity into a world of lists, inventories, and classification. The next stage is to understand their meaning.

      A notice at the top of the cliffs points the way (a quarter of it had blown away in the last gale) accompanied by a pinned-up sheet of paper instructing visitors to ‘remove footwear before visiting fossil bearing surfaces’. I confess that the idea of taking off one’s boots in a howling squall to safeguard fossils that had survived since the Precambrian had its funny side. In the event we are provided with a pair of rather fetching blue over-socks. Visits to the famous fossils are now strictly supervised, as the site is now part of the Mistaken Point Ecological Reserve, and quite right too. Canadians are strict about protecting their national natural heritage. There is an architect-designed Visitor Centre to explain all to those who have made the trip. I climb down onto the best surface, in my special socks, and it takes a while to identify what to look for, but once they are pointed out the fossils are obvious. Any doubt that they were of organic origin was immediately banished from my mind. The fossils are strewn over the black surface of the gently dipping former sea floor almost as if laid out for the convenience of future inspections: one here, one there. The most conspicuous look like leaves or fronds, and are about the same size as a domestic Aspidistra leaf or some other showy tropical pot plant. They are pleated within, and the closer one looks the more subdivisions inside the ‘leaf’ one begins to see. Such spindle-shaped fossils are the commonest type. There are more than a thousand of them on display under the Newfoundland sky. They were named Fractofusus misrai in 2007, four decades on from their original discovery, thereby commemorating the discoverer in perpetuity in the species name. The name Fractofusus is quite descriptive – the ‘fusus’ part refers to the fusiform (spindle-like) shape of the whole organism, and the ‘Fracto’ part to the fact that it appears to have a fractal structure. Fractals, those intriguing mathematical entities recognised by Dr Benoit Mandelbrot in 1980, are shapes that seem to repeat themselves precisely when the scale is focused down to a smaller level. So, the largest primary divisions within Fractofusus are subdivided into identical-looking smaller frondlets, and those in turn into identical-looking ‘sub-frondlets’, and so on. It seems that these Precambrian organisms favoured this kind of structure; indeed, Martin Brasier of Oxford University has shown rather ingeniously that several of the organisms at Mistaken Point can be understood as a kind of three-dimensional origami played out by folding such fractal objects in different ways. But there are also some frond-like organisms that seem to be attached to the former sea floor by a kind of disc-shaped holdfast. Charniodiscus masoni was perhaps the earliest Ediacaran species to be recognised – from Charnwood Forest in Leicestershire in England, as the generic name should make clear (like Misrai, the species name is after its discoverer). The same ‘frond’ is known from a very large number of Ediacaran localities, including several in the Ediacara Hills themselves, so it is almost totemic for this early and vanished marine world. The disc is thought to have held the organism in place while the frondose part was maintained aloft in the water current. There are several additional forms from Newfoundland that have their counterparts in Leicestershire, but since the latest reconstructions of the later Precambrian world place these areas quite close together geographically this is not as surprising as it may seem at first. Some other oddities are pointed out to me, one is a kind of plate with tumid blobs arranged all over it. It was called informally ‘the pizza’. The name reminded me that in my excitement I had not yet eaten lunch, so there I sat on an Ediacaran sea floor eating a cheese sandwich, looking out to sea on a perfect day while fulmars wheeled past on a light breeze. For a palaeontologist, it doesn’t get much better than this. I realise that whatever we eventually make of these strange fractal beings, it cannot be doubted that there was a lot of conspicuous life in the later Precambrian, but apparently no relatives of velvet worms. These special fossils position a time line in our story; they offer a calibration for evolutionary invention.

      I wonder what lucky circumstances account for the preservation of the fossils. After all, they are soft bodied. They could have vanished leaving no trace. My guides tell me that the area now so often coolly fog-bound was volcanically active in those distant days. Periodic ash falls cascaded into the sea and rapidly killed off and buried the Ediacaran fauna. They point out the Charniodiscus bending over in a common direction flattened by the incoming volcanic Armageddon. I should have noticed this before. Each fossil-bearing sea floor is the record of one tragic moment for the Ediacaran animals, though it is no less than a miracle for us intelligent primates. Volcanic rocks have another property in addition to their role as natural undertakers; they yield minerals that can be used to obtain a radiometric age for the eruption. They both write

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