Labels:text | paper | font | publication | document OCR: DNA (deoxyribonucleic acid) is a collection of atoms that contains all the instructions needed to construct and operate a living organism. Many people are fascinated by the question of whether any dinosaur DNA could have survived. If it has survived, could it be used to recreate dinosaurs? Scientific research shows that it is extremely unlikely that dinosaur DNA could have been preserved intact. It is even more unlikely that dinosaurs could be recreated today from any DNA found. There is still a great deal that we do not know about DNA. As yet, scientists have not been able to reconstruct a mammoth from frozen DNA a mere 10,000 years old, and the most recent dinosaur lived 65 million years ago. Despite the overwhelming evidence against the likelihood of finding dinosaur DNA intact, some people like to believe that it is possible. One theory of how DNA could have been preserved is explained here. BLOOD-SUCKING INSECTS Mosquitoes, midges, and certain other flies sometimes bite into our skin and suck our blood. Evidently, some dinosaurs suffered as well, and were prey to the ancestors of these blood-sucking insects. The dinosaur blood swallowed by these flies would have contained blood cells, which in turn contained DNA. TRAPPED IN AMBER Suppose one of these ancient biting flies landed on a nearby pine tree just after feeding on dinosaur blood. Pine trees exude thick, sticky resin from cracks and wounds in their trunks. The biting insect could have been covered by a large blob of resin that suddenly dribbled down the trunk. Death would have been rapid, not allowing time for the fly to digest its final meal. The fly would not rot away because it was encased in the resin, away from the air and bacteria that normally decompose dead animals. Over millions of years, the resin would harden and fossilize to form a block of clear, yellow amber. The trapped insect would remain intact and preserved. FROM DNA TO DINOSAUR? If the block of amber were discovered today, it could be cut open and and the insect's intestines containing its last meal could be removed. Dinosaur DNA could be extracted from the remnants of blood in the fly's intestines. This could then be transferred into some cells that would then multiply to produce a clone (an exact copy) of a dinosaur that died many millions of years before. A fascinating prospect, but in reality this has not been possible. In practice, the DNA that has so far been extracted from insects preserved in amber has been a mixture of DNA from more recent organisms.
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