There is a blood curdling roar from somewhere in the distance. Screams, more roars. We are standing, to all intents and purposes, on George Street, central Edinburgh, and dinosaurs are walking amongst us. Running, perhaps more accurately, on either side. Sometimes a big one comes and chases the others away. “Hey!” shouts a child as one of them chews a lamppost. That last roar, it turns out, does not come from one of these dinosaurs but a surprisingly small girl, who is doing her best to outgun a T-Rex. And then we emerge into a room full of dinosaur skeletons, for this is the new Tyrannosaurs exhibition, on worldwide tour from the Australian Museum, making its only scheduled European stop in Edinburgh.

I say skeletons, but these are largely casts of course (including the Canadian "Scotty", one of the largest complete T.rex's ever found), standard procedure in a museum world in which noone really wants to drill holes in their rare “complete” skeletons to prop them upright. As someone who grew up visiting the (cast) diplodocus in the Natural History Museum, awed by its sheer scale, I can't say I mind – although its fascinating, too, to see examples of the real thing, peppered about in glass cases, including the bones of the first T.rex excavated. Even the coprolites (fossilized dinosaur poo) are resin casts, surprisingly, but then fossilized bone itself is just a version of the original, mineralized very much into something that is no longer the bone a dinosaur had, but a reformed version of it.

Tyrannosaurs tells the story of the loosely connected family of familiar, upright, stalking, terror beasts that have sparked the imagination of generations of children and adults, not least demonstrated in the B movies of the 1960s and '70s, as T.rex's variously stalk the modern earth, emerging from behind Antarctic ice sheets or remote islands to terrorize scantily clad ladies and men in tights, as nuclear rockets rain in to largely futile effect. It's all on the wall here in a series of film posters from the time, entitled “The Lost World” (commuters beware!) or “Planet of Dinosaurs” (rayguns helpful). There are comics too, mingling war and dinosaurs. The men fight, the women faint, largely, which more or less puts tyrannosaurs as the direct descendants of dragons in the evolution of storytelling.

You can see where the terror springs from in the vast and heavy heads of the tyrannosaurs around us, the powerful hind legs, the sheer bulk of these giant carnivores. Perhaps more surprising is the sheer variety in size in this divergent family grouping that went through 100 million years of evolution and 25 different species (to date). The Tyrannosaurus Rex, the king of the North American continent, was the last evolutionary step before the meteor that wiped out the giants. Down in the South, the Abelisaurs ruled.

And this is a serious exhibition, full of fascinating facts and the latest research and discoveries, from the techniques of finding and uncovering these rare skeletons to the people who made it their life's work. Here are bone hunters, past and present, excavating gigantic tibia from stone-littered uplands, from curious rocky landscapes that seem the very definition of a post-apocalyptic, barren landscape, once the fire and brimstone has subsided. Here is a part of the hip bone from the very first Tyrannosaurus excavated in 1902 by American paleontologist and fossil hunter Barnum Brown, otherwise known as “Mr Bones”. Opening the exhibition, the small, colourful feathered Guanlong Wucai, discovered only in the last decade in China, existing 95 million years before the T.rex – and on the other side of the world.

There is a lot of multimedia in this show, the usual interactive displays – including a popular one in which one must hatch tyrannosaurs, drag them on to a family tree, then decimate them with a meteor – the hatching and hurling were the most popular bits from my observation. Later on children interact with dinosaurs on a screen, watching them on cctv. Every now one of the cast dinosaur shadows moves, to various screams from around the room.

And it is the casts (and the information about the finding of the bones from which they were cast) that are impressive, displaying the sheer heft of these thunderous beasts, their heads vastly oversized, their front legs, in the case of the T-Rex, so small they can't even use them to help eat their food. Noone has ever admired a T-Rex for its table manners.

I ask a small person, who is not lured by the mulitimedia, what he likes about the show. He drags his eyes away from a piece of fossilized hip bone and fixes me with a serious stare. “I just like bones,” he says, before telling me about the conjoined nasal bones of the T-Rex which helped it eat its prey without fracturing its skull. Behind us, the roars and screams continue, a child wails, the general cacophony of the first opening Saturday is all around. But one future palaeontologist stands transfixed.

Tyrannosaurs, National Museum of Scotland, Chambers Street, Edinburgh, 0300 123 6789 Until 4 May, Daily 10am - 5pm

Critic's Choice:

With the moon in conjunction with Venus as I write, it seems an auspicious time for An Lanntair to open its second Hebridean Dark Skies Festival. Then again, there's always something interesting happening in the dark above our heads, particular on Lewis which has some of the darkest skies in Europe, should the clouds clear for long enough to give us a glimpse. This wide-ranging festival, this year in memory of Scotland's Astronomer Royal, John Brown, covers everything from the inklings of a new Karine Polwart show (“The Only Light was Stars”) to a travelling Planetarium and star-gazing events across Lewis.

In visual arts, OPTIKS will bounce photos and other memorabilia off the moon by radio waves – rather like a parallel to Katie Paterson's Earth-Moon-Earth, but with family photos instead of the Moonlight Sonata. Artist Daniela de Paulis developed her Moonbounce technology whilst in residence at Holland's Dwingeloo Telescope.

In the gallery, Gillian McFarland and Ione Parkin exhibit artworks created in collaboration with astrophysicists, cosmologists and planetary geologists – this is Deep Time in mixed media, the planetary realized in blown glass (courtesy of glass artist Graeme Haws). Rust prints track orbits, geological processes inform the painted line. Next weekend, the exhibition opens with “A day of curiosity and creativity,” a day of “collaborations and conversations” between artists and astronomers. The day includes talks by Dr Amaury Triad, Astronomer, who has discovered over 100 exoplanets, and a conversation between Kate Bernstein, the book artist, and Royal Astronomical Society Library, Dr Sian Prosser. On 11th Feb, you can even go drawing in the dark, with Mairi Gillies, in the grounds of Lews Castle.

Hebridean Dark Skies Festival, An Lanntair, Kenneth Street, Stornoway, Isle of Lewis, 01851 708480, 7 – 22 Feb, Mon – Weds, 10am – 6pm, Thurs – Sat, 10am – Late.

Don't Miss:

Last chance to catch Calum Colvin this weekend for this celebratory retrospective of the artist's work. It coincides with the publication of a new book by Tom Norman,The Constructed Worlds of Calum Colvin: Symbol, Allegory, Myth,studying Colvin's photography, and celebrating 40 years of the artist's working life. Known for its complexity, its range of references, its wit, Colvin's photography takes centre stage in the exhibition, its subject matter ranging from the everyday to the art historical. Colvin overpaints his tableaux of household objects with ideasfrom myth or popular culture, leaving a photograph of parts that requires attention and interpretation.

Calum Colvin, Royal Scottish Academy, Academicians Gallery and Finlay Room, Princes Street, Edinburgh, 0131 624 6110,www.royalscottishacademy.orgUntil 2 Feb, Mon – Sat, 10am – 5pm; Sun, 12pm – 5pm