According to some authors, the DF covers a much larger area (about 300,000 km 2), extending as far as the Northwest Territories. 8 The formation is described as prograde, based on a coarsening-upwards grading from clays to sands to gravels, interpreted as the result of the changing relative deposition location from off-shore to near-shore. The Dunvegan Formation (DF) is interpreted as a deltaic complex of Cenomanian age, advancing into the sea about 400 km from NW to SE (from British Columbia to Alberta), over about 2 million years. The Dunvegan Formation such sequences bear little resemblance to the complex and irregular geological profile of modern-day river deltas. 7 Doubling the number of taxa on the grounds of footprints, which most probably belong to already-known taxa, is unlikely to make our understanding of dinosaurs simpler and more accurate. Interestingly, these were described as marine in origin until dinosaur tracks were recently discovered in them! 5, 6Īs would be expected, the most dynamic area of ichnology deals with dinosaurs, and the number of paleontological names, or ichnotaxa, is rapidly catching up with the already bushy taxonomy of dinosaurs. Despite the united efforts to dismiss the subaqueous origin of the Laoporus, one cannot forget the case of the formations in the north-eastern Bighorn Basin in Wyoming. Despite the difficulties explaining away this evidence for a wet environment, many geologists still interpret the Coconino Sandstone as a desert formation! 4 Most creationists believe the geomorphology of the Coconino Sandstone and other formations found in the Grand Canyon, with their perfectly conformable flat contacts, massive areal extents and limited thickness (in relation to its extent, the Coconino is thinner than this page), represents a continental-scale Flood deposit, i.e. Most paleontologists attribute Laoporus to amphibians, many of the features of which resemble the tracks that salamanders, manoeuvring in shallow water, produced during experiments. 3Īnother example is Laoporus (‘stone tracks’) from the Coconino Sandstone in the Grand Canyon. So names like Baropezia fontis emerged designating an unknown ‘heavy-footed (broad-toed) creature from the Fountain Formation’ (Carboniferous of Colorado).
Thus, trace fossils, like body fossils, are given individual Latin names using the Linnaean binomial system, even though the trace in itself does not represent a unique organism. This lack of matching between extinct animals and fossil tracks has led to a multiplication of fossil names. Thus the animals that left the fossil tracks are usually unknown or guessed at. And often the creatures, the bones of which are most common in a given geological setting, have left few or no tracks (as in the case of ceratopsids 2). There are millions of extinct-animal traces and tracks (ichnites), but there are extremely few skeletal remains (in the case of vertebrate ‘authors’) on the track-bearing layers. There is rarely a problem in finding the ‘authors’ of the tracks of present-day animals, but when it comes to the fossil tracks of extinct animals, the problem is much more difficult. Interestingly, people who study tracks of present-day animals are generally described as ‘trackers’ however, when the study becomes scientific the name turns into ‘biophysicist’. Map of the Tumbler Ridge area with the locations of the most important ichnofossil and fossil discoveries (click for larger image)
While some paleontologists see the study of animal tracks as a ‘lunatic fringe of paleontology’ 1 pursued by bands of enthusiastic amateur track hunters, most paleontologists recognize ichnology as a worthwhile endeavour and a valid branch of paleontology. Ichnology (Greek ίχνος ichnos = footprint) is the science that deals with the tracks, trails, burrows and other traces left by living animals, and in many respects could be compared to forensic science. The discoverers of these ichnofossils also found some of the best dinosaur trackways in Canada, described for the first time in this paper. Human-like footprints were recently discovered in the area, too, but on closer examination they seem to be metatarsal dinosaur footprints. The area near Tumbler Ridge is one of the few locations in the world with dinosaur footprints and dinosaur bones on the same bedding plane. The Upper Cretaceous Dunvegan Formation of British Columbia has yielded some of the best dinosaur footprints in Canada.
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