All dinosaurs were on the road to becoming warm-blooded, with steps towards faster metabolic rates and very high body temperatures somewhat after the origin of birds.
For theropods where we can see soft tissue, we can see insulating feathers. They grow fast – we know from cutting up bones – faster than reptiles (including those from the same period), but not quite as fast as modern birds or mammals. Growth rates and insulation are the smoking gun. We can think of dinosaurs as more bird-like than reptile-like.įor dinosaurs closest to birds – or, in fact, dinosaurs in general – we have so much evidence that suggests they were warm-blooded, short of actually sticking a thermometer in one. Reconstructions have moved on a bit since Jurassic Park… Artists have only recently let go of scaly, reptilian-like depictions. They couldn’t fly, so the feathers could be to do with display. Close relatives are better-preserved and show a complete body covering, ranging from down to quill feathers. The skeleton has quill knobs on the ulna (wing bone – also found on today’s birds).
We can confidently think of Velociraptor as having a bird-like feather covering, even though its fossils only preserve the bones. Were the Velociraptors in Jurassic Park covered in feathers? But those that could, flew in a range of different ways – suggesting early evolutionary experiments of flight, with birds being the most successful of those experiments, and persisting to the present. Not all of the dinosaurian close relatives of birds could fly. Its fossil has preserved soft tissue with a bat-like wing membrane. Also, Yi qi was discovered in the last couple of years. Fossils like this suggest the intriguing possibility that birds evolved from a gliding ancestor that had effectively four wings. It’s the Late Jurassic where we start finding really interesting, distinctive, bird-like dinosaurs – especially with recent fossils from China preserved in fine-grain sediments from lake beds.Īnchiornis is a Late Jurassic winged dinosaur, with large feather arrays on its legs. Others closely related to birds, like Velociraptor, can be from the Late Cretaceous (100-66 million years ago), so they’d also had a lot of time to evolve independently. Archaeopteryx, discovered in 1861, was for a long time the only truly bird-like dinosaur – it’s from the Late Jurassic era (150 million years ago). Theropods are all bipedal and some of them share more bird-like features than others. If feathers evolved in dinosaurs, what is the origin of birds?īirds belong to the theropod group of dinosaurs that included T. It was found preserved in volcanic ash falls – a bit like Pompeii – captured curled up in a sleeping position very similar to how a lot of birds roost today. Rare fossils also give us glimpses of the behaviour of bird-like dinosaurs, such as Mei long, a small, duck-sized bipedal dinosaur from the Cretaceous era. Many dinosaurs had not just some kind of body covering, but distinctive bird-like feathers.
The strong evidence doesn’t just come from fossilised bones and similarities found across the skeleton, but from fossilised soft tissue – especially feathers. There’s no longer really any doubt that birds are a type of dinosaur. He explains why ‘dinosaur’ is more ‘incredible bird’ than ‘terrible lizard’…Īre birds really dinosaurs? Is it disputed? Professor of Palaeobiology at the University of Oxford, Roger researches the evolution of dinosaurs – including bird origins – and large-scale evolutionary patterns. Such are the revelations from fossil discoveries in recent decades that are changing how we see birds today. Combined with short, muscular arms ending in a single giant claw for digging, Shuvuuia deserti (meaning ‘desert bird’) is not what you might classically expect from a dinosaur.
Roger Benson’s latest paper features a feathered, chicken-sized, bird-like dinosaur revealed to have the hearing ability to rival a barn owl – a specialised nocturnal predator.
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