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Whatsapp A Tyrannosaurus rex takes a morning stroll with commuters in Martin Place, Sydney

According to John Pickrell, the editor of Australian Geographic and and author of new book Flying Dinosaurs, we live in a golden age of dinosaur discoveries. The most important of these may be that the dinosaurs didn’t die out when an asteroid hit earth 66 million years ago. In fact, they still live among us... as birds.

Imagine, if you will, a world filled with billions of dinosaurs. A world where they can be found in thousands of shapes, sizes, colours and classes in every habitable pocket of the planet. Imagine them from the desert dunes of the Sahara to the frozen rim of the Antarctic Circle, from the balmy islands of the South Pacific to the high peaks of the Himalayas.

You don’t have to imagine very hard. Dinosaurs didn’t die out when an asteroid hit the Earth 66 million years ago. In fact, wherever you live, you can probably step outside and look up into the trees and skies to find them: birds are dinosaurs and they are all around you.

We have learned more about dinosaurs in the two decades since Jurassic Park than we did in the thousands of years before it.

Everything I was told as a child was wrong.

The idea takes some getting used to. On the face of it, birds don’t seem that similar to dinosaurs—they’re small, bright, quick and covered with feathers, whereas the dinosaurs I was told about as a kid were hefty, lumbering beasts much more like a crocodile than a bird. The clues were there all along, however. Theropod dinosaurs (the bipedal, carnivorous variety) share more than 80 small skeletal features with birds—far more than either share with any other group of animals.

An early clue to the link between theropods and birds came with the discovery of the first fossil of Archaeopteryx in a Bavarian quarry in 1861. It has been called the most important fossil ever found, not least because of what it told us about dinosaurs.

Labelled the ‘first bird’ this prehistoric animal had wings and feathers, but also the long bony tail and teeth of a reptile—its similarity to Compsognathus, a small dinosaur found in the same German limestone, was remarked upon at the time by British evolutionary biologist Thomas Henry Huxley.

It had only been two years since Charles Darwin had unveiled his theory of evolution by natural selection in On the Origin of Species, and perhaps the world wasn’t yet ready for the revelation of the link between dinosaurs and birds.

That connection would remain largely obscured until 1964, when Yale University palaeontologist John Ostrom stumbled upon the fossils of several lithe, athletic and deadly-looking dinosaurs called Deinonychus in the badlands of Montana. Ostrom resurrected the idea that Archaeopteryx was closely related to theropod dinosaurs such as Deinonychus, and so began the ‘dinosaur renaissance’ of the 1970s, which saw leading experts argue that dinosaurs were intelligent, speedy, warm-blooded creatures similar to birds.

The idea that birds were the direct descendants of dinosaurs still had its detractors, but much of the opposition fell away in 1996, when the fossil of a little dinosaur from China shook the very foundations of palaeontology.

Related: Dinosaur bonanza in Queensland

Sinosauropteryx was undoubtedly a dinosaur, but the fossil clearly showed that it was covered in a fuzzy down (which later studies revealed would have been ginger-coloured). This was the first of the feathered dinosaurs to be discovered, but whole flocks of them have since burst onto the scene; we now have evidence for feathers of some kind in more than 40 species. Most hail from the 100–145-million-year-old Early Cretaceous rocks of China’s north-eastern Liaoning Province, which preserve fossils in remarkable detail.

Discoveries of feathered dinosaurs are coming thick and fast these days. Just in the past few weeks alone, there have been announcements about a new 'four-winged' species Changyuraptor yangi, a new fossil specimen of the Archaeopteryx, and a feathered Siberian species, Kulindadromeus zabaikalicus.

Every new fossil is a small pebble of proof in an avalanche of evidence confirming that birds are the descendants of the theropod dinosaurs and that these animals were incredibly bird-like.

Beyond confirming the dinosaur–bird link, the fossils offer clues about how feathers evolved in the first place, and how they might have been used for flashy display purposes and insulation long before they ever helped any creature become airborne.

There is now good evidence that most carnivorous theropod dinosaurs, even fearsome and well-known types such as Allosaurus and Tyrannosaurus had feathers, and that they used them for a variety of functions.

Feathers are so intimately entwined in our minds with flight that the idea takes some getting used to. Nevertheless, animals with flight feathers can't have appeared from nowhere, so it makes sense that the earliest feathers had another purpose entirely.

The majority of the new feathered dinosaurs have been discovered in north-eastern China and Mongolia, though there have been a smattering of finds in Germany, Madagascar and North America.

Though most of the dinosaur species for which we have confirmed evidence of feathers hail from China, we can be pretty sure that dinosaurs all over the world had feathers.

This is because the feathered Chinese species come from various branches of the dinosaur family tree some of them are early members of lineages that had descendents all over the world.

The reason we can see feathers on many fossils from the north-eastern Chinese province of Liaoning is because there is a very unusual level of preservation there thanks to fine-grained volcanic ash. More than 90 per cent of fossils in the rest of the world preserve just hard tissues, such as teeth and bones—but those in Liaoning often include soft tissues such as internal organs, skin impressions, and delicate and beautiful traces of the feathers surrounding them.

Related: Victoria's forgotten volcanoes

Perhaps some of the most exciting new discoveries, however, are those that hint at how dinosaurs did eventually take to the skies. We now know that the dinosaurs most closely related to birds were small predatory species, a number of which—Microraptor, Anchiornis and Xiaotingia—had four wings and a long, feathery tail. Their hind limbs and tails had flight feathers of the kind we see today only on the forelimbs of birds, so it’s likely they used them to glide between the trees of China’s swampy Cretaceous forests.

We also now know that dinosaurs were bird-like in many other aspects of their physiology and behaviour. From nesting, brooding and sex, to metabolism, development and even the diseases that afflicted them, many of the traits found in birds today were inherited from the dinosaurs. The boundary between dinosaurs and birds has become utterly blurred.

The new fossils have brought renewed interest in dinosaurs and fresh interpretations of how they lived their lives. In 1993, when the film Jurassic Park hit cinemas, nobody could have predicted that we might one day be able to guess what sounds dinosaurs made or the colours they were decked out in, but clever new methods have begun to probe these kinds of details too.

Starting in 2010, a whole series of studies have been able to make educated guesses about the colour of dinosaur feathers by looking at tiny structural details of fossilised feathers under the microscope. In the feathers of living birds, pigments are packaged up in small parcels which vary in shape depending on the colour, and it turns out the same was true in prehistoric feathered animals.

In terms of vocalisations, we can be relatively sure that dinosaurs didn’t make the kind of mammal-style throaty growls and roars which Hollywood typically depicts. This is because neither birds nor crocodiles—dinosaurs’ closest living relatives—have vocal cords, as mammals do. Dinosaurs likely sounded like birds, though slower and deeper, seeing as they were much larger animals.

We have learned more about dinosaurs in the two decades since Jurassic Park than we did in the thousands of years before it.

The 1990s seemed like a golden age of dinosaur discovery, but fossil finds since then have been even more impressive. Around one new species is currently discovered every week, many in China, but others in South America, Mongolia and Africa. There’s so much new knowledge it’s hard to keep up, but one thing’s for certain: if you love dinosaurs, this a great time to be alive.

How does Australia fit into this picture of new dinosaur discovery and could our continent ever yield feathered dinosaurs? It already may already have. A fossil site near the town of Koonwarra in Gippsland has rocks made of fine-grained sediments and a very unusual level of preservation.

Starting in 1961, a series of 12 fossilised feathers were found here, all dating to between 115 and 118 million years ago, during the Early Cretaceous period. It was assumed that these were bird feathers, but in light of all the new discoveries from China, it is now just as likely that they are dinosaur feathers.

Flying dinosaurs Find out more about the golden age of dinosaur discovery by listening to the full episode of Ockham's Razor.

Researchers led by Dr Tom Rich at Museum Victoria in Melbourne now have plans to return to the site to search for the remains of entire feathered dinosaurs in 2017.

Australia and Antarctica are the continents were the fewest dinosaur fossils have been discovered. Australia only has around 17 known species, and many of these were described from single fragments of bone. More species of dinosaurs have been found in single quarries in China than have been found on our entire continent.

Australia’s landmass is geologically ancient, but it’s also flat and heavily weathered, which makes it very difficult to find fossils. The best places to find fossils are in mountain ranges and hills where freshly exposed rocks are eroding, but these fossil hunting sweet spots are few and far between Down Under.

There’s no doubt that part of the reason we have so few dinosaurs is because of Australia’s unusual geology, but limited funding for museum scientists and palaeontologists is also part of the reason. As a nation we have no more than a handful of vertebrate palaeontologists spread very thinly over a vast area.

In comparison, China has an army of diggers out there right now, which is why their stunning fossils are fuelling the current golden age of dinosaur discovery.

If Dr Rich is able to secure funding for his Gippsland expedition in 2017, there’s a chance of finding incredible feathered dinosaur fossils in Australia too—and what a coup for scientific discovery that would be.

Ockham’s Razor is a soap box for all things scientific, with short talks about research, industry and policy from people with something thoughtful to say about science. John Pickrell is the author of Flying Dinosaurs: How Fearsome Reptiles Became Birds and editor of Australian Geographic.



