If the Burin Peninsula is a boot, the two old fishing towns of Fortune and Grand Bank rest firmly on the toecap.
It’s a long way down there – about three hours’ drive from the Trans-Canada at Goobies – and many Newfoundlanders I’ve met have never made the journey. Those that have were typically heading for France.
All of which is a great pity, as there are many good reasons to visit this historic and hidden part of the island. The Seamen’s Museum in Grand Bank is one of my favourites, not least because it is improbably housed in the Yugoslavian pavilion from Montreal’s Expo ’67.
Top of the list, however, for anyone of a geological persuasion is Fortune Head Ecological Reserve. For as unlikely as it might sound, this cliff-top sanctuary is the place where animal life officially began.
Life layer writing
Geological time is founded on fossils. When 19th century scientists were trying to work out the age of the Earth, they realized that different fossils appeared systematically through the different layers of sedimentary rock.
Two pioneering Englishmen, William Smith and his nephew John Phillips, showed that although the types of rocks in a layered succession could be repeated – sandstone upon sandstone, shale upon shale – the fossils could not. One species would be found in a series of layers and then disappear, with a different species taking its place.
By recognizing this pattern, Smith and Phillips invented biostratigraphy, or life-layer-writing, recording the order in which different fossil groups came and went. All units of geological time are founded upon it – from the Jurassic period to the Mesozoic era – and rocks right across the world can be correlated by using it.
Neither Phillips nor his uncle made it to Newfoundland, but their principles did. In the old marine rocks that cover much of the island, biostratigraphy has been repeatedly applied, and many key boundaries defined. The most important of all is at Fortune Head.
The origins of animals
In purely geological terms, this Burin bootcap boundary is the GSSP (Global Stratotype Section and Point) for where the Precambrian stops and the Cambrian begins. In the 1990s, having examined comparable rock successions across the globe, scientists decided that Fortune Head was the best place in the world to observe the transition.
However, the real importance of the juncture is what it represents to life on Earth: the appearance of complex animals. Being one myself – at least occasionally – I feel that’s a pretty significant event to commemorate, and something more Newfoundlanders should be aware of.
As the wondrous fossils of Mistaken Point vividly reveal, there was life in the Precambrian. It was the Cambrian period, though, when animal life underwent an explosion. Sea creatures suddenly started doing all sorts of new things.
One of the new things – and the one for which Fortune is now famed – was the ability to burrow. For biostratigraphy, this is quite odd. Normally, a new period of time is defined using body fossils, such as shells and teeth. In the case of the Precambrian-Cambrian boundary, it’s trace fossils that are the markers.
Now I may be an ichnologist and prone to bias, but the development of vertical bioturbation is one of the most revolutionary events in Earth history. Prior to its evolution, marine life was two-dimensional. Creatures sat on the sea floor, or crawled over it.
Competition for food and resources, however, began driving an evolutionary arms race. Whether hunters or the hunted, around 542 million years ago, animals started to penetrate the sediment: first shallowly and simply, then more deeply and complexly. The acquisition of muscles played a key role, as did the development of teeth and guts.
Buried nutrients were released, oxygen brought down into the substrate, and new habitats and ecosystems created. A third dimension was opened up, and the world changed forever.
The worms that turned
If you are to inspect the rocks at Fortune Head (and, indeed, at nearby Grand Bank Head, where ancient Earth movements have repeated the succession), you can see this happen before your very eyes, only half-a-billion years after the event.
In the lower rock layers, there are trails of various shapes, but they all meander across horizontal surfaces. Then, if you get your eye in, you’ll spot the critical change. The burrows begin to go up or down in the beds: some branching, some spiralling, some pipe-shaped, some U-shaped. None of them are huge, but they’re hugely important.
Under the rules of biostratigraphy, only one gets to be diagnostic. That lucky trace fossil is Treptichnus pedum, or ‘the turning trail shaped like a shepherd’s crook’. Scientists still argue about its name, exactly how it was made, and by what. A recent study has suggested it was the feeding trace of a priapulid worm.
Regardless of all this, there is little debate about the importance of Treptichnus and its ilk. They were pioneers, doing something that had never been done before, and they left their legacy in the rocks of Newfoundland.
So although it might never be a destination that’ll bring the tourists flocking in, we’re lucky to have Fortune. There is nowhere else on Earth that you can place your hand on a rock ledge in a cliff-face and say with authority, “This is where animal life really started making its mark.”