Spinosaurus aegyptiacus – Kem Kem Assemblage
Spinosaurus aegyptiacus with jaws agape trawls for mesozoic fish. Reconstruction of the Cretaceous ecosystem recorded in the Kem Kem beds of Morocco. Illustration by Brian Engh under the scientific guidance of Tor Bertin.
The big gnarly looking fish in the foreground are of the genus Lepidotes, reconstructed based primarily on L. maximus. These fish had rows of flat peg shaped teeth adapted for crushing mollusks, and the one foremost in the frame is eyeing an aquatic snail grazing on the algae-covered driftwood. In the background a couple large predatory tarpon (Cladocyclus pankowskii) can be seen gliding along stealthily. In the foreground observing everything is a giant side-necked turtle (Galianemys whitei). Further back in the frame, swimming around the Spinosaur’s hip area are some small fish that we shall say are of the genus Diplomystus. Between the two spinosaurs another Galianemys swims. In the foreground in front of the background Spinosaur a lungfish (Ceratodus humei) patrols the bottom for molluskan prey, ambling along on its leg-like fins. Just right of the lungfish two large cretacious gar of the genus Oniichthys survey their domain. Way in the back just to the right of the background Spinosaur, a school of Lepidotes and a sawshark (Onchopristis numidus) flee in the wake of the Spinosaur’s piscivorous predation. In the air above the Spinosaurs flies and dragonflies buzz about as Tepejarid and Siroccopteryx/Coloborhynchus pterosaurs soar majestically above.
I did this illustration for a paper being published by a paleontologist named Tor Bertin. It was super exciting to work with a scientist on a paleo illustration for the first time. He provided me with the science that made reconstructing this environment possible as well as the grounding to keep my imagining of these animals vibrant and believable without becoming overly speculative or sensational.
Obviously Spinosaurs are really weird looking dinosaurs, so for this illustration I was attempting to imagine them in a behavioral routine that made sense of their very strange anatomy. It is clear from spinosaur teeth and jaw structure that they have adaptations specific to catching fish, and there is evidence in their bone chemistry that Spinosaurs spent much of their time submerged in water. Also, it appears that spinosaurs had pressure sensing pores in their jaws, similar to crocodiles. These pores allow crocodiles to hunt by sensing the movements of fish in the water around their jaws. All that makes sense for a fish eating predator… So why a huge sail?
The best I can do here is speculate based on the observable behavior of extant animals. It occurred to me that crocodiles, grizzly bears (particularly when hunting salmon runs) and hippos might be good analogues for Spinosaur behavior. All are large, territorial animals that spend some (bears), most (hippos), or nearly all (crocodiles) of their time in rivers. As a result they all do a lot of territorial posturing to defend their stretch of the river. Bears, bellow and stand on their hind legs, hippos vocalize, raise their head and bear their tusks, and crocodiles do a lot of subtle body posturing with their back and head, as well as some vocalization. Of course with crocs a lot of these behaviors are more subtle because stealth above the water is key to their predatory success. Spinosaurs don’t appear to have been well equipped for killing anything other than fish, so a huge display structure above water wouldn’t have hindered their success as hunters. Rather, it might’ve allowed them to broadcast their body language further while at the same time keeping those sensitive fish-trap jaws down in the water hunting. It could also have helped display to mates. In all, it would’ve allowed Spinosaurs to communicate with body language above the water, while still actively hunting below the water. This would’ve increased food intake and decreased combative encounters while at once helping to attract mates. All of which would’ve contributed to greater survival for the individuals with big beautiful communicative sails.
That’s what I was thinking when I drew this, anyway… Let me know what you think.
Thanks for stopping by!
Wilmar on 23 Apr 2010 at 4:42 pm #
Dude, this is righteous.
Mark on 26 Apr 2010 at 5:44 pm #
VERY cool depiction of Spinosaurus. Love the Cladocyclus pankowskii in the background!
marnie on 28 Apr 2010 at 10:31 am #
Awesome…. times five million and then multiply THAT by, like, at least fifty.
“Mark” wins in the comment department though!
Fonz on 28 Apr 2010 at 5:13 pm #
Wowee, Wowee! This looks really fantastic Brian. I really LOVE the illustration but what I enjoy the most, and this goes for all of your work, is how much you research and really understand your subject, then how you let that inform the creative decisions you make on the piece. It’s really encouraging and inspires me even more to find new ideas and ways of doing things creatively through science and nature.
Historian on 28 Apr 2010 at 9:52 pm #
I love comments!
Thanks guys!
Yeah Mark wins in the comment department – that fish is actually named after him.
No, seriously, Pankowski is his last name. He loves collecting fossils and he bought the original fossil from a fossil dealer and then donated it to the Smithsonian because he recognized that it was something special. The Smithsonian then sent it to a paleontologist named Dr. Peter Forey of the Natural History Museum in London. Dr. Forey then named the fish after Mark to honor his generous contribution to science.
That dude doesn’t mess with dinosaurs (or prehistoric fish, for that matter).
Zach on 30 Apr 2010 at 8:07 am #
hey man for some reson the lmu blog wont let me comment on your post. Anyway, not that you dont know by now but this thing is fuckin awesome. i want more dinosaur paintins from you man. ever seen dinotopia by james gurney? i want a dinotopia from you!
Historian on 23 Jun 2010 at 3:39 am #
my dinotopia would not be peaceful. theropods contained to the rainy basin? c’mawn!!
Old Toothy Pictures: A Review of Spinosauridae by Tor Bertin « The Optimistic Painting Blog on 11 Dec 2010 at 5:51 am #
[…] is a great illustration in the paper of Spinosaurs fishing by Brian Engh, as well as cool skeletal restorations by Scott […]
HungerArtist on 25 Dec 2010 at 3:10 am #
this is one of my favorites so far!
DARLENE GONZALES on 22 May 2013 at 3:05 am #
Thanks for the cool info. my son and I learned alot. He has a project due, and this was the largest dinosaur byfar. thanks again :)
Historian on 22 May 2013 at 6:34 am #
Darlene,
I’m glad you found my post informative. Did you mean to say the largest meat-eating dinosaur? Spinosaurus was definitely not the largest dinosaur. Compared to some of the giant long-necked Sauropods, Spinosaurus was relatively small. In fact some species in the Sauropod group likely weighed more than 10 times as much as the largest Spinosaurs!
Spinosaurus is First Known Semi-Aquatic Dinosaur - D-brief | DiscoverMagazine.com on 11 Sep 2014 at 6:00 pm #
[…] Spinosaurus aegyptiacus trawls for mesozoic fish. Illustration by Brian Engh […]
Sci Guy on 12 Sep 2014 at 12:00 am #
No. The sails were to use sunlight to warm the blood after being in cool/cold water for extended periods.
Historian on 12 Sep 2014 at 2:52 am #
Well, you’re welcome to think that, but I don’t know of any Spinosaur experts who agree with you. The time and place where Spinosaurs lived was extremely hot and humid, so if the sail had any thermoregulatory function it was likely to shed heat, something like the expanded ears of elephants, fennec foxes and many other modern hot-climate animals. Also, if you look at the habits of living semi-aquatic reptiles, such as turtles and crocodiles (who are ectotherms and therefor much more dependent on thermoregulation than warm blooded animals like dinosaurs) they tend to thermoregulate by either basking in the sun, going for a swim, or burrowing underground. The few that have sails or frills (basilisks and sailfin lizards) appear to only have them for display purposes. Overall it seems there is more of a precedent in reptiles and birds for gaudy display structures, and most Spinosaur researchers I know tend to think this is the most likely explanation for their bizarre sail.
Le spinosaure découvert au Maroc: premier dinosaure semi-aquatique connu – L'écologie au Maroc on 20 Apr 2016 at 11:22 am #
[…] Spinosaurus aegyptiacus chassant des poissons mésozoïque. Illustration par Brian Engh […]