A helicopter skims over the surface of a dark, rough sea. "I own an island off the coast off Costa Rica," says the voice of billionaire John Hammond. "I've spent the last five years setting up a kind of biological preserve."

This is the trailer for one of the most successful films ever, Jurassic Park. And among the images flashed in front of our eyes is a mosquito trapped in amberFossilised resin - which is the viscous (thick, sticky) liquid inside a tree that protects it from external threats. Amber has been appreciated for its colour and natural beauty since Neolithic times..

In the film, a mosquito preserved in this way has sucked the blood of a dinosaur. John Hammond's team manage to isolate the DNADeoxyribonucleic acid is the material in an organism that carries genetic information. in the blood and use it to clone the creature it came from.

The December issue of Current Biology has a similar mosquito on the cover. The amber containing it is 125 million years old.

Scientists knew mosquitoes had been around far longer than humans. But they were unsure when the insects first emerged, and whether they fed on blood.

The mosquitoes in amber are 30 million years older than any previously found. This means they could have had ancestors in the JurassicThe geological period between 200 and 145 million years ago when dinosaurs diversified and became the dominant land animals. period.

The fact that they have piercing mouthparts suggests that they sucked blood - and could have fed on dinosaurs. 

Jurassic Park's director, Steven Spielberg, says the film could not have been made if the science were not believable.  

There are problems, however. DNA is measured in units called base pairs. Humans have three billion. Dinosaurs could have had 10 billion. But none of the DNA found in fossils has more than 250.¹

Even if enough base pairs were found, putting them together in the right order would be incredibly hard - like sticking together a book which had been cut up into single letters.

On top of that, DNA is known to degrade over time. The oldest found so far - in the teeth of mammoths preserved by the Siberian permafrostAny ground that remains completely frozen for at least two years. Permafrost covers large regions of the Earth.  - is around one million years old.² A dinosaur's DNA would have had to survive for 65 million.

Yes: In recent years scientists have made extraordinary progress in extracting DNA, mapping genomes and cloning. Future discoveries could well make Jurassic Park possible.

No: Nobody has yet managed to find dinosaur DNA. Even if they did, and it had not degraded too much, they would not be able to recreate the creature as it actually was - just an approximation of it.   

Or... It would lead to disaster if it did. As one of the scientists in the film says, "Sometimes we get so preoccupied with whether we could, we don't stop to think if we should."