You may not have noticed, but 2020 completely changed the way we view Spinosaurus. Scientists have speculated for decades if it was a terrestrial animal or if the crocodile-like snout, with all its typical adaptations for fish eaters, meant that it was semi-aquatic. There was even speculation that its sail was used for herding swarms of fish into a "bait ball", because it looks exactly like the sail of some swordfish, who use it for the exact same thing. Nobody could tell for certain, though, because the only known Spinosaurus skeleton was incomplete, and also had been destroyed in an air raid in WWII. Paleontologists had nothing to go by except for the drawings of this lost specimen. It took until the 1990s until new Spinosaur fossils were found in Egypt, Morocco and Tunisia, but all of these were fragmentary.

Things took a change recently, though. A nearly complete tail and some other missing parts were found in the Kem Kem fossil beds in Morocco, and they revealed that Spinosaurus not only had shorter hind legs than expected, but also a keeled, paddle-like tail as we see nowadays in some sea serpent species. A robotic model has now shown that it enabled a way of swimming that was both fast and energy efficient. Given that so many other large carnivores like Carcharodontosaurus lived in the same area at the same time, it makes sense that they occupied different niches in their ecosystem of tidal flats and mangrove forests, and Northern Africa had an abundance of prey for a semi-aquatic giant dinosaur at that time, as you can see from the picture. All of these animals where found in the same formations as Spinosaurus fossils, from the giant bichirs and lungfish in the upper right to the chonky coelacanth Mawsonia (no. 5) and the sawfish Onchopristis (no. 9).