Cosmos
Cosmos is a quarterly science magazine. We aim to inspire curiosity in ‘The Science of Everything’ and make the world of science accessible to everyone.
By Cosmos
Who doesn’t love dinosaurs? People of all ages find wonder in these incredible ancient creatures. From completely new types of dinosaurs to confirmation that some feathered dinosaurs used powered flight, we have been spoilt with palaeontology this year.
1. Australia’s smallest sauropod – a 4.2-tonne baby!
Sauropods were the giants of the dinosaur world. Famous species of these long-necked dinosaurs like Diplodocus, Brachiosaurus and Apatosaurus were among the largest animals ever. Current estimates suggest that the largest animal to ever walk on Earth was the epically-named sauropod Dreadnoughtus which was about 35 metres long and weighed up to 100 tonnes.
But even these behemoths started out as babies – only, they were big babies.
Nicknamed “Ollie”, Australia’s smallest sauropod was found less than a year after the country’s largest was found just 400 kilometres away.
Ollie was a “child” when he met his unfortunate demise 95 million years ago. But he was a chunky baby, measuring 11 metres in length, and weighing 4.2 tonnes – as much as an elephant!
2. Were dinosaurs warm or cold-blooded?
I imagine a T. rex charging at you might be considered “hot-blooded”. But new research has confirmed that many dinosaurs – like their bird ancestors – did, indeed, have warm blood.
You may be surprised to hear that finding out the metabolism of animals that have been extinct for tens of millions of years is pretty tricky. But over the last couple of decades, palaeontologists have had an inkling that many dinosaurs were in fact endothermic (warm-blooded).
I’ll spare you the details – the chemically-inclined can read up on the particulars – but palaeontologists found molecular markers in dino fossils, which they were able to compare with living creatures, to work out the extinct animals’ metabolic rates.
The new method revealed that the bird-hipped sauropods and two-legged dinosaurs like T. rex were warm- or even hot-blooded, while the lumbering lizard-hipped dinos like Triceratops and Stegosaurus were cold-blooded.
3. AI solves dino footprint mystery
Looking into the past is made easier with the development of futuristic technology like artificial intelligence (AI).
While AI doesn’t appear to be taking over the world (yet), one machine learning tool certainly did a better job of resolving a dinosaur footprint conundrum than its human palaeontologist counterparts.
Scientists were divided on whether one particular set of fossilised dinosaur tracks from 93 million years ago was made by a meat-eating theropod, or a herbivore.
After first proving to be a good judge of dinosaur tracks, the AI was tasked with resolving the debate. And it did. Looks like they came from a herbivore after all. The chance it was a therapod? According to the AI: 1 in 5,000,000.
4. Fossils found in Australian opals!
Fossils are precious enough. Honestly, I think I would prefer a fossil over any gemstone. But, as the famous Aussie taco commercial goes: “Por que no los dos? (Why can’t we have both?)”
Palaeontologists in South Australia found dinosaur bones fossilised in that most Australian of gemstones: opal. Thankfully for everyone involved, the opals in question are not all that valuable as far as opals go, so they have been secured from the mining company for science.
Cutting edge scanning technology revealed a 100-million-year-old small, plant-eating dinosaur.
Lead researcher Associate Professor Paul Willis spoke with Cosmos in a video interview about the find.
5. A new two-legged, armoured Argentinian dinosaur found
As cool as dinosaurs are, palaeontologists admit that they weren’t that varied. There are the horned ones, the long-necked ones, the two-legged ones, the lumbering, tank-like ones, and the duck-billed hadrosaurs. Apart from a few exceptions, this is a pretty comprehensive picture of all dinosaurs.
Well, 2022 saw the discovery of a dinosaur that didn’t quite fit into any of these categories.
Dug up in Argentina, Jakapil kaniukura has spikes and armour plating similar to the famous Stegosaurus and Ankylosaurus but is small and bipedal.
Breaking the mould, Jakapil expands the range of the Thyreophora group of armoured dinosaurs to the southern hemisphere. It also suggests that there may be other new dino body plans to be discovered. I’m still hoping that we’ll find legitimate dinosaurs among the fossils.
6. Controversy: Was T. rex more than one species?
Early in the year, a study suggested that the most famous dinosaur, the King, Tyrannosaurus rex was not one, but three distinct species.
Even with modern animals, taxonomy can be something of a crapshoot. This is made harder when you’re trying to classify species that lived 66 million years ago. Nonetheless, the research sent shockwaves through the scientific community. And it was promptly refuted.
The authors of a second rebuttal paper provided evidence to suggest that the claim T. rex was actually three different species, was based on inadequate statistics and limited comparative analysis.
The intramural feud of palaeontologists was short-lived and resolved (for most) in favour of the conventional wisdom that there is only one Rex. But the experience does show that palaeontology is hard and even what seem to be the most basic precepts may be challenged.
7. How a cold snap led to the Age of Dinosaurs
Popular culture tends to paint dinosaurs as reptiles associated with hot, humid, tropical environments.
But the truth seems to be more complicated. Not only have we found dinosaurs that thrived in Earth’s ancient poles, but this year saw an analysis which suggests that it was actually dinosaurs’ adaptation to the cold that gave them an advantage over the ancient reptiles that ruled when dinosaurs first emerged around 230 million years ago.
In fact, dinosaurs were bit-part players in the early Triassic when they first appeared, relegated to the colder regions of the prehistoric supercontinent Pangaea. Early feathered dinosaurs may have led the way.
When they were no longer able to adapt to the changing environment – likely propelled by Pangaea’s eventual break up – the ancient reptiles went extinct, leaving the Earth to the dinosaurs who ruled for the next 150 million years.
Turns out dinosaurs are pretty cool after all.
8. Powered flight confirmed in Chinese dinosaur fossils
A study of more than 1,000 fossils of flying feathered dinosaurs found in north-eastern China this year was the first to provide direct evidence for powered flight.
Researchers were able to come to their conclusions thanks to fossils discovered which preserved some soft tissue of the ancient flappers. Strong shoulders allowed these first flying, feathered friends to power upstrokes in flight, while chest muscles powered their downstrokes.
One of the species, Confuciusornus, was named after the ancient Chinese philosopher Confucius, known for his pearls of wisdom.
“Our greatest glory is not in never falling, but in rising every time we fall,” said Confucius, advice which allowed his namesakes, the flying feathered dinosaurs, to take to wing.
9. Streamlined body helped a semi-aquatic dino swim
An unusual dinosaur with a streamlined body and many teeth was discovered this year. It is the first dinosaur to have such a body shape, clearly adapted for diving in the water, like a cormorant.
The semi-aquatic dinosaur, named Natovenator, was found in what is now the deserts of Mongolia. But in the late Cretaceous (100 million to 66 million years ago), Natovenator was diving for fish in freshwater lakes and rivers.
A far cry from the “classic” dinosaurs like Tyrannosaurus and Triceratops, Natovenator shows that dinosaurs were probably more diverse than we may give them credit.