In the "Jurassic Park" movies, dinosaurs are brought back to life after scientists find dino DNA in the bellies of millions-year-old mosquitoes preserved in amber. Even though resurrecting the animals never turns out well in the movies, that doesn't keep the fictional scientists from continuing to bring them back sequel after sequel.

And if the movies got it right about anything, it's probably just that. If real-life scientists had the chance to clone a T. rex, is there any doubt that they'd do it in a heartbeat? A real-life Jurassic Park has got to be every paleontologist's — as well as every young dino-fanatic's — dream come true. 

So where are we on the science of cloning dinosaurs? What's taking the scientists so long? Let's have a look at the actual science behind the dream of Jurassic Park.

What about amber?

Though the premise in the movies sounds plausible, that dinosaur DNA might be found in amber-preserved mosquitoes, the reality is far more complicated. First of all, dinosaur blood has never actually been found in mosquito fossils, not even a teeny fraction of it. So such a discovery, as represented in the movies, is pure fiction. Secondly, the odds of ever finding such a fossil are pretty much nil. This is because fossilization in amber is a relatively rare event.

If it ever happened that a female mosquito (females are the only ones that suck blood) with a belly full of recently-slurped dinosaur blood did get immediately encased in amber, this rare fossil would then have to survive 60-plus million years into the present day. Time is not the only limiting factor; the fossil would also need to have remained in perfect condition over that period of time. In other words, it's simply a fool's errand to hang hopes on finding such a well-preserved fossil. 

So you're saying there's a chance?

Unfortunately, no. Even if scientists did beat the insurmountable odds and find a mosquito fossil with dinosaur blood in it, it would still be impossible to extract DNA from it. Why? Researchers have recently discovered that the DNA half-life is 521 years. (Interestingly, they calculated this by studying DNA inside the 8000- to 600-year-old bones of extinct, giant birds called moa, that once strode over New Zealand. These giant birds might as well be called "avian dinosaurs," as scientists now know that birds evolved from dinosaurs.)

While that might seem like a long half-life, it's not even close to being long enough to account for the timescale needed for the preservation of dino DNA. Even under ideal conditions, the entirety of a creature’s genome will be obliterated within 6.8 million years. So we're already 59-plus million years too late to find any of T. rex's DNA. 

Other methods

It's safe to say that any method of resurrecting dinosaurs that relies on finding preserved DNA, such as portrayed in the movies, isn't going to happen. But might there be other ways?

One remote possibility is that scientists might one day develop a way to reverse engineer DNA. For instance, perhaps our knowledge of creation would become so advanced in the future that we could start with an idea of a creature, and then artificially build the genetic structure for that organism from scratch. Scientists might be helped on this venture by the fact that dinosaurs do have modern living kin — birds. Though diluted immeasurably over the course of evolution, there might remain some genetic hints there, at the very least.

To be clear, though, such technology is way beyond the limits of modern science — way, way beyond. In fact, such a feat seems downright fantastical at this point. But given a few thousand (million? billion?) years of technological advancement? Maybe then, dinosaurs — or at least some approximation of dinosaurs — could be recreated.

Next best thing?

Though a Jurassic Park is unlikely to happen any time soon, a Pleistocene Park might make for a nice consolation. The Pleistocene is the geological epoch which lasted from about 2,588,000 to 11,700 years ago — fairly recent by geological timescales — and DNA from extinct animals alive during this period is not only possible to find, it has been found. Scientists have managed to extract partial DNA from the remains of woolly mammoths, Neanderthals and giant sloths, for instance. Though none of these creatures have been cloned yet, attempts are being made to do so. There is even a nature preserve in Siberia which has been named Pleistocene Park, where scientists are attempting to recreate the ecological conditions of the era.

So with any luck, the fantasy of resurrecting recently extinct animals and creating a nature preserve for them could become reality. It may not satisfy our itch to walk among dinosaurs, but it might be the next best thing.

Let's just hope that if it happens, woolly mammoths and saber-toothed tigers won't overrun their enclosures and hunt down the zoo patrons, as the movies always suggest they inevitably must.

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Bryan Nelson ( @@brynelson ) writes about everything from environmental problems here on Earth to big questions in space.

Will scientists ever clone dinosaurs?
'Jurassic Park' movies make it look inevitable, but will dinosaurs ever actually walk the Earth again?