The Great Roar of Time
As the Jurassic period ended, the long-anticipated shift in time had materialised and welcomed the age of the biggest dinosaurs and creatures to ever walk the Earth. This was the Cretaceous Period. Through the minor mass-extinction that occurred in the Jurassic period, the longest period of the Mesozoic Era had begun, which lasted for 79 million years and dated 65.5 million years ago.
In the Early Cretaceous, the continental arrangements were vastly different from the arrangements in the present. The continents of the once huge Pangea were gradually drifting apart and over time the sea levels became much higher than it is now. If we were to visualise it, you’d see that most of the landmass in present day would be submerged in water! However, at the end of the Cretaceous, two huge lands assumed the shapes which we now know as Africa and South America. However, the lands that make India and Asia had not collided yet, with Australia concurrently still being part of Antarctica.
This period was truly a sight to behold ranging from masses of new plant life with the introduction of the first flower plants, and the humungous Titanosaurs that dwarfed even the largest Diplodocus in both size and masses alongside the world-renown, terrifying predator the Tyrannosaurus Rex, which literally translates to the ‘Tyrant Lizard King’.
The Titanosaurs were incredibly massive Sauropods that succeeded the Diplodocus and the rest of its genus which were the last long-necked dinosaurs to survive before the final annihilation of all the dinosaurs. Amongst its relatives of Brachiosaurids and Euhelopodidae, the Titanosaurs were the bigger cousins and thus were obviously humungous, with the biggest of their species, Argentinosaurus having proportions of 20-40m in length, 60-88 tons and perhaps the largest ones even stood at a ridiculous height of 20m. These were truly titans and makes us by comparison look like very miniscule insects.
As mentioned in the previous articles, like their Sauropod predecessors, they ingested huge amounts of plants, leaves and branches before being mechanically digested by smooth stones called Gastroliths to grow to their insane sizes, but these Argentinosauruses never stopped growing in their entire lifetime. Starting from their eggs, it has been researched that it took approximately 15 years to grow into their adult sizes, 25,000 times bigger than the Argentinosaurus hatchlings. Considering that these eggs were around 20 cm in diameter, it’s extremely mind-blowing for any person without actually seeing their skeletons to imagine how incredibly huge they were!
However, with so much flesh and prey like these herbivorous giants, as always, there are predators that adapt to match and hunt them. Allosaurs were large Theropods adjusted to hunt the giant Diplodocuses and other dinosaurs, making them apex predators of their respective food chain. However, what could possibly match these far larger and heavier Titanosaurs? They were the Carcharodontosaurids, a group of terrifyingly titanic killers, armed with incredibly sharp, serrated teeth and grasping claws and lived around almost throughout the whole cretaceous period. One such notable individual: the Carcharodontosaurus, was a colossal monster, being four times as big as the Allosaur and the largest discovered one having greater proportions than the even biggest Tyrannosaurus Rex, which for a time was what the world believed to be the biggest land predator of all time.
The Carcharodontosaurus was, through thorough research, approximately ranged between 12-13.3 m long (39-44ft) and weighed between 6.2-15 tons. Its most notable feature could perhaps possibly be its teeth, with each tooth having serrated edges. These particularly shaped teeth, growing up to 8 inches long, allowed it to pierce and tear off flesh like knife through paper, and its methodology in hunting involved letting their prey to bleed out while stalking them patiently before the prey died by blood loss, resulting in more stamina reserves. They hunted Paralititans, Sauropods that were similar in sizes to the Argentinosaurs as well as the Ouranosaurs, a subset of a group of duck-billed dinosaurs called Hadrosaurs. These Ouranosaurs were pretty large too, being approximately 7m long and weighed 4 tons. It has to be stressed that, since the Carcharodontosaurus lived in North Africa, it had competition for food with not just other Carcharodontosauruses, but also another titanic predator, the Spinosaurus. If you thought there was a predator that couldn’t get bigger than the Carcharodontosaur, let alone a Trex, then you’re wrong.
The Spinosaurus was a monstrous colossus, having proportions between 12.6-18m in length [41-59ft] and 7-20 tons in weight. To further enhance its physical appearance, it had a large sail on its back [most likely for thermoregulation especially in the African heat], which gave it an intimidating and overbearing look to all creatures in its vicinity. Having crocodilian-like jaws, its snout was sensitive [useful for hunting] and its jaws were longer than that of the Carchorodontosaurus, and from all this you’d think if they clashed, it’d be a no-brainer that the Spinosaurus would win by its sheer size and threatening long arms that had the potential for it to crawl on all fours.
However, its teeth were meant for grasping [especially for the fish they usually hunted] rather than slicing and tearing apart flesh like those of the Carcharodontosaurus, meaning its bite was not as of a threat. Its long arms, however, compensated and could scratch away other dinosaurs at range. These clashes between titans could have gone either way to the death and, and despite its gory, thrilling and action-packed fights, in this aspect it allows us to be thankful that they no longer exist today! This feeling of awe yet gladness can be established by the recent films of Jurassic Park and Jurassic World where we encounter a world if dinosaurs were to be restored and live alongside us.
Obviously, Argentinosaurus lived in what we now know as Argentina, it was hunted by Mapusaurs and Giganotosaurus which were similar in size to the Carcharodontosaurus with similar characteristics, and hunted in packs to take them down especially the younger, smaller and older ones, as we know these predators are always opportunistic. The Gigantonosaur has always been a subject of interest for Paleontologists as there are no full skeletons or majorities of one identical Giganotosaurus, and thus many predictions had to be made to give a rough idea of its size. These predictions have shown that the Gigantonosaur had the potential to be even bigger than the largest Carcharodontosaurus, leaving the question of the sizes in order of the greatest and largest predators to ever walk the Earth. This places the Tyrannosaurus Rex in 4th place.
Over time, the Carcharodontosaurids slowly died out as well as the Spinosaurus due to climate change and the lack of freshwater for the Spinosaurus to hunt its primary source of food fish, made it suffer from malnutrition and cause more titanic battles for food with the dying Carcharodontosaurus. However, around 30 million years later, it was the Tyrannosaurs that dominated the Earth. In North America where the biggest type of Tyrannosaur, the Tyrannosaurus Rex [Trex] lived, there weren’t many titanosaurs for it to hunt. So if there weren’t much of these colossal herbivores to hunt, how did the Trex thrive and get to its fearsome and enormous sizes?
Being the biggest predator in North America, it was relatively unchallenged by other predators and the apex predator though research did show that it was a scavenger too. That meant it had more access to food, and specifically, these were the Edmontosaurus, Triceratops and the Ankylosaurus. Edmontosaurus was a Hadrosaur, similarly to Ouranosaurs, and were huge, with some being 12m long! Though this provides some insight into why the Trex grew to its frightening size, what made it so fearsome? Other prey like Triceratops and Ankylosaurs, were heavily armed for defences: Triceratops had three horns on its head to spear into impending carnosaur threats, while the Ankylosaurus itself had plates of armour and a clubbed tail on its back to smash predators into smithereens!
These defensive herbivores were not small either. The Triceratops by length was in the range of 7.9-9m long, and weighed around 6.1-12 tons, whereas the Ankylosaur, a tank of a herbivore and the largest of its kind the Ankylosaurids, grew up to 6.25m in length, 1.7m in height [at the hip] and weighed from approximately 4.8-8 tons! As these were thriving herbivores, the Trex needed to hunt them for survival despite the obvious huge risk hunting them posed. These risks greatly pushed the Trex hunting capabilities to the limit and beyond, resulting in more precision in their attacks to ensure they sank their teeth into the two herbivours’ weak points.
Furthermore, the Trex had a bigger brain than the Carcharodontosaurids, and thus were smarter, being more advanced hunters than the other predators that were said to be bigger than it. However, its best-known feature was that it had the strongest bite of all land predators ever in history. Whilst the Carcharodontosaurus and its brethren had serrated teeth to tear flesh and had a medium-strength bite, the Trex’s jaws and teeth were built to crush bones and in this case, greatly helped in killing the armoured and deadly herbivores. Alongside its still spectacular proportions of 12.5m [40ft] in length, 3.66m [12ft] tall at the hips and weight of 8-18.5 tons, it was a stocky predator with a thick neck, and its small 2 fingered arms were actually quite muscular and strong. The biceps of the adult Trex could lift 199kg, and allowed it to keep struggling prey down before fatally biting it, and all this just goes to show how terrifying it truly was, regardless of its size.
The Cretaceous also bore incredible life other than the huge dinosaurs. It was this period where the first flowering plants first developed. These flowering plants were Angiosperms, and through insect pollination, they fluctuated. The oldest Angiosperm fossil discovered which dates back around 122 million ago, was thought to be similar to the modern Black Pepper Plant. Some herbivores like the Ankylosaurus would have these Angiosperms in their diet though there is still limited evidence that many dinosaurs ate them. The climate itself was considered a warmer place than before too. Over time, it got hotter as evident by the dying Spinosaurus and Carcharodontosaurus in Africa near the late Cretaceous.
In addition, there were many large monsters that lived in both Seas, lakes and rivers. Such examples are the Mosasaurus and Sarcosuchus. Mosasaurus was a carnivorous aquatic lizard and the largest of its kind the Mosasaurids, reaching lengths of 17m [56ft]. With a large, robust skull and a lower jaw tightly connected to it, it had a powerful bite, and with flippers for limbs, easily swam around near the surface of the sea which was its hunting ground for turtles, fish, birds, ammonites, plesiosaurs and even smaller Mosasaurs. They were huge and definitely dwarfs the biggest Great White Sharks. There was also the Sarchosuchus, which hunted in murky rivers and lakes.
They were gargantuan Crocodiles, being approximately twice the size of the largest crocodiles, the Saltwater, and could reach lengths of approximately 12m and snout lengths of 5.7m. Having 132 large conical teeth, these massive predators could hunt fishes, other crocodilians and even dinosaurs too! It is evident that a young Nigersaurus of the Diplodocid family was eaten by one meaning it must have been huge to be able to do that. Furthermore, it had the ability to compete for food with even Spinosaurus and Carcharodontosaurus, and thus proves that it was incredibly fearsome too!
However, all this…was eventually lost. Around 65.5 million years ago, the Cretaceous period was ended as previously mentioned, but due to the K-PG extinction event. This occurred when a gigantic asteroid hit the Earth, and wiped out nearly all large vertebrates and many tropical invertebrates, and was a geological, climatic and biological event with worldwide consequence, with the initial hit causing a multitude of huge shockwaves and Tsunamies, clouds of hot dust to form and block the sun in the atmosphere for many years.
The cloud of hot dust ‘cooked’ and overheated the dinosaurs alive, while smaller creatures could hide underground and potentially survive the initial heat. Additionally, the hot dust prevented much sunlight from entering the Earth, killing the plants and creating a dystopian world and a long nuclear winter. It cannot be accentuated enough how powerful the impact was as the crater site is more than 110 miles in diameter.
This was the harbinger of the end of the Mesozoic Era, but it does not lessen the fact that the Cretaceous period was a hallmark of Earth’s history and it truly was a great roar of time. However, it also resulted in the birth of a new age: The Cenozoic Era, a world no longer full of dinosaurs, but gained new life that is just as spectacular too!