Palaeontologists have discovered the remains of an enormous dinosaur believed to be one of the largest animals to ever walk the planet – Dreadnoughtus schrani, named after the dreadnaught battleships which were said to “fear nothing but God”.
As detailed in a recent study published in Nature, the first of the remains were discovered back in 2005 on a trip to a barren scrubland in southern Patagonia. Since then, over one hundred bone fragments have been unearthed, making this also the most complete dinosaur skeleton ever recovered.
Dreadnaughtus is thought to have roamed the earth approximately 77 million years ago in the southern parts of South America. It’s believed that this particular Dreadnoughtus weighed nearly 60 tonnes – that’s roughly equal to the weight of 12 African elephants, or seven Tyrannosaurs rex. The length from its snout to its tail measures an impressive 26 metres, a metre longer than the longest Diplodocus found so far, and making it the longest land animal on record.
Despite its shockingly large proportions, the research team concluded that it was not fully grown when it died. The lead author of the study, palaeontologist Kenneth Lacorvara of Drexel University, told the Guardian: “That was a real shock to us. When you look at the bones of Dreadnoughtus, it’s clear this individual was still growing fast. There are no indications of a cessation of growth.”
It took more than four years to excavate the bones, which later worked out to be over 70 per cent of the animal’s skeleton. Similar prehistoric giants include the Argentinosaurus and the Diplodocus, but, while those species are only known by a small number of unearthed bone fragments, Lacorvara and his team obtained more than one hundred well preserved Dreadnaughtus fossils – including a single tooth and a small section of its jaw. This was a great discovery, since giant herbivore skulls are usually small and light in comparison with their bodies to let the animal lift its head, and consequently they tend to be destroyed rather easily instead of becoming fossilised.
During the Cretaceous period – towards the end of the time before dinosaurs became extinct – the site in which the remains were discovered is believed to have been as a mixed forest with rivers, prone to flooding. This would have turned flood plains into sinking sand, and unfortunately for this particular Dreadnoughtus it was simply at the wrong place at the wrong time.
The scientists also describe a bite mark on one of the Dreadnoughtus’ vertebrae, and assume it to be from one of the meat-eating predators – also discovered at the scene – feasting on the dinosaur’s corpse before it was completely immersed in sand. Once the scientists pieced the remains together, the fossils presented an image of a huge animal with a muscular 10 metre tail, an even lengthier neck, and on each its back feet, three huge claws. The tail would’ve been used as a weapon to protect itself – which raises the question, what on earth would such a gigantic animal need to protect itself from?
The fossils will now be scanned with lasers so that the researchers can build robots which mimic the way the dinosaur will have moved when it was alive. “A dinosaur in this mass range, 65 tonnes, is really pushing the limit of what is physiological possible,” said Lacorvara in a video announcing the discovery. “It would be hard to understand this dinosaur from a very fragmentary skeleton, so we’re very fortunate, we have nearly a complete skeleton of this amazing creature. This is going to help us understand the frontier of physiology in terms of super-massive land animals.”