Science could follow sci-fi in bringing back creatures of the past

SCIENCE FICTION fantasy films often present us with resurrected creatures from the past - such as in Jurassic Park and the movies it inspired like the Carnosaur series and the dreadful Sabretooth.

Most recently, the prehistoric epic 10,000BC brought to life the mammoths, sabretooth tigers and giant predatory birds that once walked the Earth.

Documentaries, too, such as Walking with Dinosaurs and its follow-ups (Walking with Beasts, Cavemen and Monsters) have all reconstructed long-gone species.

But a lot of it is educated guesswork. We don't know what colour dinosaurs were, for instance. Or how exactly the sabretooth used its huge fangs.

Theories and knowledge change over time. It's now believed many dinosaurs were covered in feathers, as shown in this image of a model of a Deinonychus (a clawed predator much like the velociraptors of Jurassic Park) in the natural history museum in Vienna, which I visited last year.

The creature looks amazingly different with the plumage put on it by the museum's scientists - although we still don't know if it's really how Deinonychus looked.

Recently, New Scientist reported that it may be possible in future to recreate many extinct animals. But resurrecting dinosaurs is probably not possible, despite what we saw in Jurassic Park, as the DNA hasn't been preserved over the 65million years since they died out.

More recent beasts preserved in ice are much more likely candidates. Science could one day recreate any creature that lived within the last 100,000 years, as long as it was trapped in permafrost (or tar pits) and had hair, because low temperatures and hair shafts protect DNA.

Researchers in the USA recently put together the genome (DNA structure) of the woolly mammoth and a German team has nearly finished assembling the genome for Neanderthal man.

Reviving ancient species would probably involve inserting key genes into the egg of a close living relative to create an embryo that could be implanted in the living creature. For instance, a mammoth embryo could be put into a modern elephant, a Neanderthal embryo into a chimpanzee, a sabretooth into an African lion, a woolly rhino into a modern rhinoceros.

The DNA of the Tasmanian tiger, a marsupial predator which was hunted to extinction out 70 years ago, is even more readily available because museums around the world have specimens preserved in alcohol.

But there is little chance of revival for the glyptodon - an armadillo the size of a VW Beetle that once trundled across the South American plains - because its modern relative, the armadillo, is so small by comparison and an embryo couldn't reach full term. However, there is no glyptodon DNA available yet anyway.

There is DNA for the giant ground sloth but, similarly, its modern relative the three-toed tree sloth is far too small to carry the embryo.

DNA is in short supply for the dodo so it's likely to remain the symbol for something that's well and truly dead.

With a wait for the science to be available, not to mention the debate over ethics and the lack of availability of some DNA, it looks like moviemakers might still have plenty of creative licence in the way extinct creatures look on the big screen.