Michael E Howgate (UK)
Back in the days when I gave my ‘Doctor Dinosaur’ talks to museums, school groups and ‘gifted children’, I would take with me: a plaster cast of the Baryonyx claw; a beach rolled Iguanodon vertebra; and, star of the show, ‘a fossilised dinosaur poo’ (which, in reality, was an Ichthyosaurus coprolite from Lyme Regis). These were some of my collection of props, which helped engage the children through what might otherwise have been a run-of-the-mill slide presentation.
Some of the bits-and-pieces I picked up to pass around among the children were a selection of broken and hence dirt cheap Carcharodon megalodon teeth (Fig. 1). (I use Carcharodon instead of the more correct Carcharocles as it is still in common use. The term ‘Megalodon tooth’ is often used by fossil dealers as a short-hand term.) These stood in for the teeth of every child’s favourite dinosaur, the fearsome Tyrannosaurus rex. I would pass the teeth round and get the children to feel the serrated edge as a prelude to explaining how a serrated blade was better at cutting steak – or even a loaf of bread – than a sharper carving knife. “Only try this at home if you are supervised by both parents” was my health and safety rider at the end of this explanation.
Carcharodon (now Carcharocles) megalodon, which used to be considered the ancestor of the great white shark, Carcharodon carcharis, is now thought to be more closely related to mackerel sharks, hence the change of name. Despite this demotion, the status of C. megalodon as the apex predator to end all apex predators, plus the size and symmetrical beauty of the teeth, has made a perfect, hand-sized Megalodon tooth a must have for many a status-driven fossil collector (Fig. 2).
Most of the specimens you are likely to see on dealers tables are the large, sub-triangular, shiny, jet-black examples, which come from Miocene deposits of the south-eastern United States, especially South Carolina, Georgia and Florida. Most of the ‘Megalodon’ teeth that appear at fairs have been fished out of stream beds and pools, where they have been eroded out of the soft sediment. There are lots of U-tube clips of local collectors picking up stunning finds from the most unprepossessing of muddy backwaters and ditches. However, most of the teeth they find are small run-of-the-mill sharks’ teeth or broken and chipped larger ones. These are almost worthless to a fossil dealer.
The gold standard is the perfect, unworn, pristine example, with every denticle of the cutting edges in place. And then size is everything. The only worn examples worth collecting and hence dealing in are the historic ones collected in the Victorian era from the Basement Bed of the Red Crag in Suffolk. But that is another story entirely.
The demand for large and even medium sized pristine examples is increasing and, even specimens with a few missing or damaged denticles, still command a good price. However, the marketplace is flooded with broken and chipped specimens, such as the ones I tended to purchase. But, in a group of broken and otherwise damaged teeth I picked up for a song from a collector/dealer several years ago was one very odd specimen indeed.
As far as I was concerned, it was useless. The serrated edges had been worn away, so it was no use for my T. rex feeding demonstration. It was an odd shape as well. Where the broken pieces I generally saw were split down the middle this one had both sides removed symmetrically from the root up to the enamel cover cutting edges, giving it a spear point shape (Fig. 3). It went into a plastic bag with a basic label, then into a box of odds-and-sods to be looked at later.
Several years later, last year in fact, I was in need of a large flint arrow-head for a talk I was preparing on the ‘Uses of Flint’, when I came across a website on ‘Clovis’ points. These are the dramatic spear points produced by Native Americans and, just by chance, there was a link to ‘Shark Tooth Blades’ and an image of my Megalodon tooth appeared.
Shark tooth blades are, according to the Peach State Archaeological Society website:
… primarily a Florida artefact, but may apply to any coastal environment, especially if natural stone is not readily available.”
So, while ‘Clovis-type points’ were being produced where outcrops of tough chert could be quarried, in the coastal regions of the south-eastern United States, tools and weapons were being fashioned from the teeth and bones of fishes, and even the tail spines of king crabs. The teeth of the extant lemon shark (Negaprion brevirostris) seem to have been preferred for drilling holes in other teeth; while the teeth of the snaggletooth shark (Hemipristis serra) were suited for wood carving. tiger shark (Galeocerdo cuvieri) teeth were nearly always perforated at the base of the crown so that they could be hafted (that is, attached to a handle or ‘haft’) for use as saws or clubs.
Some authorities believe that this tooth and bone culture pre-dated the ‘Clovis point’ culture by about 1,500 years, dating it to 15,000 BP, thus making it the earliest culture in the Americas.
Of the two C. megalodon teeth illustrated in the ‘Shark Tooth Blades’ sub-section of the website of the Peach State Archaeological Society (see above for link), one was described as a dart point and the other was thought to have been used as a pendant to be worn around the neck. A study by Laura Kozuch of Palaeo-Indian shark tooth blades from three sites in southern Florida cited 841 shark tooth blades, only 11 of which were made from fossilised teeth and only two of these were the teeth of C. megalodon. Thus, they are exceedingly rare.
|The things to look for on a shark tooth to establish its Palaeo-Indian artefact credentials are:|
|(1) Holes drilled at the site of the nerve pit, which is at the top of the root of the tooth, where it meets the enamelled crown. These were drilled from both sides using the point of another shark tooth as a bit and are thus hour-glass shaped in cross-section. This is possible because, although all of the tooth is made of apatite (calcium phosphate), the enamel that covers the tooth crown is harder than the dentine, which is exposed in the root area.|
|(2) Abrasion of the rounded or bulbous surface of the labial side of the tooth, to flatten it and make it a better ‘spear’ point.|
|(3) Filing of the edges of the tooth to remove the lateral denticles. This turns a ‘sawing edge’ into a piercing blade more suitable for a spear-point.|
|(4) Removal or rounding of the tooth roots. In C. megalodon teeth, this provides a hafting area for the spear-point to be fixed to the wooden shaft.|
|(5) The blunting or rounding of the tip. This may often be caused when a tooth is used as a drill.|
My C. megaladon tooth blade is 10cm long, by 4.5cm in maximum width, by 2.4cm in maximum thickness. The lower part of the enamel cover crown, along with the adjacent root area, has been removed from both sides of the tooth and the denticles along the margins of the tooth have been substantially eroded to leave a sharp blade-like edge on both sides. The tooth is substantially similar to the one illustrated on the Peach State Archaeological Society website as figure 2, on page 6 of the section on ‘Shark Tooth Blades’ (see above for link). There is extensive spalling (that is, breakages into smaller pieces) of the enamel of the crown on the labial surface, which does not appear to have been caused by the working of the tooth.
The shape conforms to what is described in the literature as a ‘dart’. However, due to the bucco-labial (see below) asymmetry of the tooth, it is unlikely that it would have been the point of a throwing spear, as it would have been unbalanced, but it would have made the point of a serviceable thrusting lance.
Near the base of the tooth root are two series of small holes, one on the buccal (that is, towards the tongue) surface and the other on the labial (that is, towards the lips) surface. The holes are deliberately placed so that they do not line up: the three holes on the lingual surface are above the five on the labial side (Fig 4). The most likely explanation for this arrangement is that the holes were placed in this off-set fashion to retain the strength of the tooth root when it was attached to a metal shank, to be re-used as an ornamental pendant.
My particular thanks are due to Lloyd E Schroder, webmaster of the Peach State Archaeological Society and author of ‘The Native American Toolbox’, who confirmed the identification of my C. megalodon tooth as a Palaeo-Indian artefact, although he did not agree with all of my interpretations. Most of the information on Palaeo-Indian artefacts has come from the website of the Peach State Archaeological Society – in particular, the sub-section on ‘Shark Tooth blades’ (see above for link).