Ferocious Dinosaur Moments | Top 5 | BBC Earth

a carcass will attract every big predator for miles around [Music] attracted to the feast it is more than capable of challenging for the carcass [Music] [Music] [Applause] [Music] [Music] majungasaurus has short arms and can't grasp tyrannosaurs it's all about the bite [Music] the shape of majungasaura's skull and teeth suggests a very different biting style to the flesh-tearing dinosaurs with a broad short and muscular skull it was a dino better adapted to biting and gripping rather than slashing its prey this fight is about more than just winning the feeding rights to a carcass [Music] when the

bite marks on the mall majungasaurus remains were studied more closely the marks on the bones were found to match the only large carnivore in the region there is no bigger killer in these lands than majungasaurus this is the first irrefutable evidence of dinosaur cannibalism [Music] it might seem shocking but it's a behavior that clearly shows the most successful killers will exploit any situation to their maximum advantage a time when both egg and the brooding parent are permanently at risk [Music] smaller oviraptors are no more than a nuisance larger predators are a different story unwilling to

leave the nest the adult protects its offspring first by hiding and if that fails it goes on the offensive [Music] [Music] so [Music] protecting the nest means gigantoraptors young are more likely to survive it now seems clear that the instinct to nurture and care for a nest of eggs had its origins with the dinosaurs it's a behavior that was so successful it's still widespread today with birds but the fossils show something else these animals all died sitting on their nests it seems that the threats don't always come from predators sometimes the real danger comes from

the most unlikely places [Music] these dinosaurs were all buried alive spinosaurus is a predator but one that hunts in water it's ixyophagus a fish eater this is ankapristis [Music] an eight meter long giant sawfish similar to those alive today the saw like rostrum is lined with lethal barbs and is in itself up to two and a half meters in length it's thought they migrated into freshwater rivers to breed where the young may be safer but the adults are exposed to new threats [Music] with their breeding season at its height these rivers are filled with ankapristis

it's the perfect hunting opportunity for spinosaurus [Music] spirosaurus's conical teeth evolve to grip prey rather than tear off flesh for that it needs powerful arms and claws with prey plentiful spinosaurus can afford to be wasteful a fact which other dinosaurs take full advantage of rugops an eight meter carnivore anywhere else it might dominate but here it is dwarfed by spinosaurus spinosaurus is unique with long narrow jaws and nostrils set high on its head its teeth were straight and conical they gave us a clue as to how it killed more evidence came in 2008 when spinosaurus

skull was put through a ct scanner it revealed a curious pattern of holes and sinuses in the snout that look just like those of crocodiles it's thought these contain pressure sensors sensors that like a crocodile can detect prey making it perfectly adapted to hunting in water [Music] this discovery gives us our best evidence of exactly how it hunted able to hold its snout in the water because of its high nostrils it can strike without even seeing its [Music] prey [Music] hunting on land spinosaurus is also forced into direct competition with any large predators living in

the same environment and here that can only mean one animal [Music] soros [Music] contests over carcasses are common but outcomes of such fights are far from guaranteed risk of injury for big animals is acute modern komodo dragons are often killed in fights over carcasses more than three meters longer spinosaurus has size and power on its side [Music] but carcaradontosaurus has the more lethal bite [Music] this time the spinosaurus triumphed [Music] but the balance of power between these two deadly killers is a precarious one [Music] in 2008 a spinosaurus vertebrae was recovered part of the tall

neural spine of the bone was broken off it appeared to have been bitten in half it's been suggested that the bite was inflicted by carcaladontosaurus spinosaurus was the last and the largest of the fish-eating dinosaurs but ultimately these specialists were doomed something way beyond their control caused their downfall 94 million years ago the climate changed global sea levels began to rise the swamps and rivers that spinosaurus thrived in gradually were lost [Music] with their loss spinosaurus's specialism became a vulnerability [Music] and the biggest predator ever known to have walked the earth [Music] disappeared [Music] [Music]

but first impressions can be deceptive this isn't the parent this is a scorpio veneta a predator [Music] the skeleton found at the nest site was almost certainly a nest raider preying on the hatchlings the hatchlings real parent and the owner of the enormous vertebra is argentina suarez a plant-eating giant that dwarfs everything around it from the bones that were found we've calculated that argentinosaurus was a colossal 35 meters long and weighed as much as 75 tons [Music] when born the hatchlings themselves weigh a paltry 5 kilograms and need to fend for themselves [Music] immediately from

studying the embryos and looking at the bones of the adults we know that the growth of these giants was phenomenal [Music] over 40 years they grow from 5 kilograms to an astonishing 75 000 kilograms at their peak it's been calculated they grow up to 40 kilograms every day the dinosaur embryos are so well preserved we can see they already have their teeth in preparation for a lifetime of eating but becoming a giant takes more than simply turning tons of food into muscle it's about the success and survival of a species over millions of years one

way to increase the chances of survival is by having lots of offspring and the best way to do that is by laying eggs lots of them the nest site in patagonia stretches for an astonishing 15 kilometers and contains tens of thousands of eggs and the site was used continuously for hundreds of thousands of years [Music] you