Is An Extinct Species of Great White Shark Still Alive Today?
Most people know that the great white shark, Carcharodon carcharias, is today’s largest known extant prehistoric fish. Or is it? My recent study of an old photo of a dead white shark, laying on a dock somewhere, suggests there may be another, related, macropredatory shark still out there.
This is the photo in question. As you can see, it appears to be a dead great white (a sad sight, one I hope we will see far fewer of as time goes by). Something about the picture struck me as odd, however. Something I began to study in detail. The teeth. At first glance, they appeared robust, which is, in itself, not an unusual thing. There are often inter-species variations in animals, with some specimens of the same genus/species of shark, albeit from different regions, having thicker or heavier tooth crowns versus others.
In this case, however, it wasn’t just the robustness of the teeth that intrigued me. It was the actual crowns themselves. I noticed what looks like a rather thick, raised region going down the center of the crowns – in particular, the principal/primary (central) maxillary (upper jaw) teeth. These are the ones used by the great white and several other species of shark when it comes to feeding. The lips peel back and the upper jaw extends up and out, hyper-extending, before coming down hard to shear through flesh and bone and excise a mouthful of flesh. (see my video here at around the 5:30 mark).
The questions that arise now are: why are this white shark’s teeth like this; is this a normal trait and if so, what purpose to they serve? The answers are as follows: IMHO, it is not a normal trait. I’ve seen many a GW tooth in my day, and never one like this. The closest I was able to find was a photo of a principal maxillary tooth from my peer and elasmobranchologist Simon De Marchi. As you can see, there is no raised region, no central column, so to speak, as appears to be in the mouth of the mystery shark. Instead, there is a crease of sorts, where the crown appears to have a faint, almost diamond-shaped, compressed cross section.
This leads us to the last part of the question: why are the teeth in the deceased shark’s mouth so labially reinforced when it comes to the central regions of their crowns. The answer is very likely, and as was evidenced by the above Vic Hislop white shark tooth – albeit to a lesser extent – an attempt at strengthening the teeth that bear the most strain during feeding. Whereas the normal GW teeth have labially flattened crowns (that means the display sides or outside faces of the teeth are fairly flat) the mystery shark’s teeth have these heavy reinforcements. This strongly suggests that the marine life the shark was feeding upon was either hard-shelled – like sea turtles – or had robust bones that often needed to be bitten through. One such possibility is the shark had a habit of targeting the extinct sirenid Steller’s Sea Cow, which was wiped out by Europeans during the mid-eighteenth century. This robust beast reached lengths of up to 30 feet and had a heavily reinforced skeleton, as shown below.
Before we get into that, an important question to ask is, do we have any examples of shark teeth that appear to match the teeth of the shark in the photo? The answer is yes, and is also the reason why I reached out to one of my peers, several years ago. This tooth, and others like it, appear to be virtually spot-on matches. But what kind of teeth are they? At first glance they look like great white shark teeth, ones that have those mysterious, column-like centers. But they’re not. They come from a type of white shark that’s been extinct for millions of years – a species called Carcharodon hubbelli. They evolved between 8 and 5 million years ago during the Late Miocene and early Pliocene epochs. The shark is regarded as a transitional species and shows intermediate characteristics that place it between the extant great white shark, which appeared around 3.3mya, and the extinct broad-toothed Mako shark, Cosmopolitodus hastalis, which hung around until around a million years ago (Early Pleistocene). Per Wiki, “C. hubbelli appears to have been geographically restricted to the Pacific Ocean.” Interestingly this was also the case of the aforementioned Steller’s Sea Cow, whose range extended across the Northern Pacific during the Pleistocene Epoch (ref. Wikipedia).
In addition to the column-like sections, visible on the labial surfaces of the crowns, there is additional evidence to support the possibility that this shark was, indeed, an extinct member of a long-gone species. The nose is pointed, perhaps a bit more so than that of a normal great white, but within what I consider accepted norms. The mouth is large, although not overly so, and the teeth large and heavy. Due to image quality, we can’t see the serrations, although they don’t seem very coarse, which, again, is a characteristic of C. hubbelli, which were finer (higher in number) and diminish in size towards the tip. These fossil teeth, courtesy of Buried Treasure Fossils, show how the serrations evolved over time. The extinct giant Mako C. hastalis had none. C. hubbelli had finer/less coarse serrations, and the extant great white has the most coarse.
Another characteristic of C. hubbelli is the layout of the teeth. Per Wikipedia: “As a transitional species, C. hubbelli possesses a mixture of features present in extinct white sharks like C. hastalis and in the extant white shark, C. carcharias. The distal inclination of the intermediate tooth is characteristic of C. hastalis, but the presence of serrations (though not fully developed) and a second upper anterior tooth larger than the lower second anterior tooth are characteristic of C. carcharias.” The distal inclination of the intermediate tooth refers to upper (maxillary) tooth number 3, which in the great white is mesially inclined, as well as normally smaller than maxillary teeth numbers 1 and 2. Mesially inclined means the tooth tilts toward the front/center line of the mouth. This can be seen in the great white jaws below.
A distally inclined tooth, on the other hand, is angled/directed toward the rear of the mouth, away from the center or midline. In our mystery shark, we see this characteristic, especially when compared to the jaws of a great white (note: the intermediate tooth in the white shark also causes a stricture in the jaws, which enables it to have a more pointed snout than, say, a bull or tiger shark. I would also point out the fossil C. hubbelli tooth featured below that appears to match the intermediate tooth in our mystery shark (ontogeny-based changes and camera angle notwithstanding), including the curved crown tip. This is, again, absent in the extant white shark, and, again, suggests that our mystery fish, with its large, centrally reinforced teeth, set in angles that are characteristic of C. hubbelli, may in fact be an example of this extinct predator.
Another characteristic of C. hubbelli is the layout of the teeth. Per Wikipedia: “As a transitional species, C. hubbelli possesses a mixture of features present in extinct white sharks like C. hastalis and in the extant white shark, C. carcharias. The distal inclination of the intermediate tooth is characteristic of C. hastalis, but the presence of serrations (though not fully developed) and a second upper anterior tooth larger than the lower second anterior tooth are characteristic of C. carcharias.” The distal inclination of the intermediate tooth refers to upper (maxillary) tooth number 3, which in the great white is mesially inclined, as well as typically smaller than maxillary teeth numbers 1 and 2. Mesially inclined means the tooth tilts toward the front/center line of the mouth. This can be seen in the great white jaws below.
In closing, although we are limited to a single photo and a plethora of fossils as evidence, after studying the combined characteristics of our mystery shark (an animal which was estimated as having been 4.4 meters in length. i.e. 14 feet 5 inches), I believe that, as shocking as it may be, there is evidence that suggests that the extinct transitional great white Carcharodon hubbelli may still be with us. Another possibility is the fish is a genetic throwback with traits that disappeared millions of years ago. Could either of these possibilities explain the fast-swimming Monster Mako shark that people sometimes report seeing? If so, our oceans just got a hell of a lot more exciting.
