(Part 3 can be found here)
When I told fellow researcher Scott Mardis about the carcass which Ms. Julie Hagan has reported, he had wondered if it could possibly have belonged to a species of relict marine reptile (although he did think a mutated beaked whale or other cetacean was more likely). He pointed out that several species of marine reptile have a similar body shape, similar flippers, and a remotely similar tail fin. He has also pointed out that, although the carcass' alleged hair could seem problematic for a marine reptile, decomposing leatherback turtle carcasses can appear "hairy" due to the breakdown of tissue fiber. With that thought in mind, comparisons will be made with four different Mesozoic marine reptile families. Thanks to Scott Mardis for creating these comparative images for me to share here.
The first comparison is between Thomas' Hagan carcass reconstruction, Ms. Hagan's sketch of the carcass she reported, and two depictions of pliosauroids. Pliosauroids were a genera of short-necked and large-headed plesiosaurs which lived in the Jurassic and Cretaceous periods.1 The reconstructions in comparison to the Hagan carcass depiction are of a very large skulled species called Kronosaurus. Kronosaurus were marine reptiles which lived in the oceans around what is now Australia and Colombia, measured around thirty feet long, and possibly had a lifestyle similar to that of a sperm whale.1 While the reported carcass shares similarities such as a bulky body shape, four flippers, and a long tail with these prehistoric pliosauroids, other distinctive features do not match. Kronosaurus did not have a blowhole, most reconstructions do not depict them with a tail fin (if they had one it would likely have been vertical), their snouts were too long, they were likely lipless like crocodilians, and they grew to large sizes meaning that the Hagan carcass would have had to be that of a juvenile. Also, as with every one of the marine reptiles referred to in this article, the fact that Kronosaurus would have had to have a ghost lineage of some 100 million years is another roadblock for their survival to today.
|Top left to right: Hagan Carcass depiction by Thomas Finley and a reconstruction of Kronosaurus. |
Middle: Reconstruction of Kronosaurus.
Bottom: Ms. Julie Hagan's illustration of the Hagan carcass.
Please click to enlarge
Next is a comparative image between Thomas' Hagan carcass reconstruction, Ms. Hagan's sketch of the carcass she reported, and a recent reconstruction of the mosasaur Platecarpus. Mosasaurs were fast swimming marine predators which thrived as the dominant oceanic predators during the Cretaceous period.1 These macropredatory animals had various specialized adaptions for hunting and consuming prey, and some species even stalked freshwater estuaries and deltas.1 Some scientists argue that the mosasaurs share a common ancestor with living snakes and lizards (squamates), and it seems that their closest living relatives are the monitor lizards.4 Many features of the mosasaurs are similar to those of the squamates, such as mobile skull bones (allowing them to swallow large prey) and a Jacobson's organ (allowing them to detect scent particles in the air or water with long, forked tongues).4 While the presence of four flippers, a streamlined body, a long tail, and an apparently short snout are similarities which mosasaurs share with the Hagan carcass, one recently discovered feature in particular stands out in comparison. In 2010, a team of paleontologists published a report on a remarkably complete specimen of Platecarpus which was excavated in the 1960s.5 The specimen exhibited traces of soft tissues such as skin impressions and a reddish residue that may be the remnants of its heart or liver, but most interesting was a feature which indicated that previous views of mosasaur anatomy were wrong.5 The tail of this Platecarpus possessed a distinctive set of vertebrae that were wider at the top than at the bottom, indicating that the animal had a downward-kinked tail which likely supported a tail fin.5 So rather than having a straight tail and an anguilliform swimming motion, mosasaurs were likely propelled by their crescent-shaped tail flukes (similar to those of the ichthyosaurs).5 A recent discovery of a fossil Prognathodon specimen which had a soft tissue outline of its fluke preserved further confirms this. While the presence of a fluke is a noteworthy similarity, the problem of dissimilarities rises once again. Mosasaurs possessed scaly skin, long snouts, tails in the vertical plane, nostrils on the snout rather than a blowhole, and other features which are quite different than those alleged to have been exhibited by the Hagan carcass. However, as with the aforementioned metriorhynchid crocodilians, mosasaurs have received much cryptozoological attention from researchers such as Dr. Bernard Heuvelmans and Dale Drinnon. Dr. Heuvelmans even pointed out that mosasaurs were the most likely marine reptiles to survive, as they belonged to a more recently formed group and were still successful at the Latest Cretaceous period.3 While intriguing sightings and the relatively recent success of these marine reptiles indicate that mosasaurs may possibly still survive, it is not likely that the Hagan carcass was representative of such an animal.
|Top: Hagan Carcass depiction by Thomas Finley.|
Middle: Recent reconstruction of Platecarpus.
Bottom: Ms. Julie Hagan's illustration of the Hagan carcass.
Please click to enlarge
The final comparative image in this article is between Thomas' Hagan carcass reconstruction, Ms. Hagan's sketch of the carcass she reported, and reconstructions of three different species of Triassic ichthyosaurs. These marine reptiles were the earliest members of the diverse order Ichthyosauria and ranged in appearance from eel-like to whale-shaped.1 These Triassic reptiles were atypical ichthyosaurs which mostly inhabited oceans in what is now Nevada.1 While these animals possessed similar anatomy to the Hagan carcass in their two sets of powerful flippers and long yet rather cetacean-like body, other feature including their tail fluke appearance, nostril location, snout appearance and length create problems for speculating that the Hagan carcass belonged to any of these marine reptile species.
Although slight features suggest similarities between the reported Hagan carcass and Mesozoic marine reptile species, this seems to be a most unlikely hypothesis as several other features are in contrast. While recent discoveries which revealed that several species of marine reptiles possessed tail flukes which do bear an intriguing resemblance to the tail in Thomas' painting and Ms. Hagan's, these flukes were vertical and thus does not coincide fully. Other problems which hypotheses regarding relict marine reptiles face are numerous; examples include the unlikely vast gaps in the fossil record that such surviving species would have left, the problem of these animals' former niches being currently held by successful species such as marine mammals, and the fact that many of the features reported for cryptozoological animals do not match with what we currently know about the anatomy of marine reptiles. Therefore, I feel that it is safe to conclude that the Hagan carcass was most likely not that of a marine reptile. Thank you to viewers of this article and other articles in the Hagan Carcass Comparison series. Make sure to keep a lookout for part five which will deal with the conclusions which I have inferred from this research.
- Dixon, Dougal. The World Encyclopedia of Dinosaurs & Prehistoric Creatures: The Ultimate Illustrated Reference Guide to More than 1000 Dinosaurs and Prehistoric Creatures, with 2000 Specially Commissioned Watercolours, Maps and Photographs. London: Lorenz, 2010. Print.
- Haines, Tim, and Paul Chambers. The Complete Guide to Prehistoric Life. Buffalo, NY: Firefly (U.S.), 2006. Print.
- Heuvelmans, Bernard, Richard Garnett, and Alika Watteau. In the Wake of the Sea-serpents. New York: Hill and Wang, 1968. Print.
- Dixon, Dougal. Visual Encyclopedia of Dinosaurs. London: Dorling Kindersley, 2005. Print.
- "The Mosasaur's Kinky Tail." The Guardian. N.p., n.d. Web. 26 Aug. 2013. http://www.theguardian.com/science/blog/2010/sep/01/mosasaur-evolution-dinosaurs.