Biomolecules and the Chemistry of Life
Pop Culture and Biomolecules and the Chemistry of Life
Jurassic Park – Science Fiction or Biological Reality?
We can answer this one right away: Jurassic Park, for all its special effects, suspenseful moments, and heart-stopping dinosaur chases through the forest, had some major scientific flaws. For one, T. rex lived in the late Cretaceous period—almost 80 million years after the Jurassic ended. Oops. Perhaps more importantly, the whole premise of the movie—that dinosaurs can be cloned from DNA extracted from mosquitoes preserved in amber—does not hold any water. For one, DNA is pretty fragile and degrades quickly once an organism dies. Even if there were enough surviving DNA to look at, it would probably be all mixed with the mosquito’s DNA. On that note, can you imagine what a dinosaur-mosquito hybrid would look like? One thing is for sure: it would have a wicked bite.
Additionally, the DNA would be so fragmentary and damaged that it would be impossible to put the pieces back together correctly. The movie dealt with this problem by suggesting that frog DNA could fill in the gaps, but frogs are completely different animals. Putting random pieces of their genetic code into dino DNA would not work. It would be like taking isolated sentences from The Sound and the Fury, filling in the gaps with sentences from Twilight, and then expecting a coherent story to emerge. Not gonna happen.
OK, so Hollywood’s scientific accuracy is…umm…questionable (the understatement of the century right there). We may not have any dino DNA, but as it turns out, a team of researchers at North Carolina State University, led by Dr. Mary Schweitzer, recently discovered dinosaur collagen, a protein common in animal muscle tissue, preserved in fossilized bone! Normally, when an animal dies, its body decays. Obvious, right? However, in very rare circumstances, an organism may become fossilized, in which case the original organic material in the body gradually is replaced by minerals. Dinosaurs lived so long ago that scientists always figured the mineralization process would be complete by the time we dug them up, but now we know that the original protein can still be intact after all this time.8,9
The first dinosaur collagen that Mary Schweitzer and her colleagues found came from a Tyrannosaurus rex that was about 68 million years old. With help from a team at Harvard Medical School, led by Dr. John Asara, they were able to sequence some of the collagen they found (they figured out the sequence of amino acids in a T. rex's collagen). They found that the amino acid sequence of the T. rex was more similar to a chicken than it was to any of the other animals they tested, lending support to the idea that dinosaurs and birds are closely related to each other.8,10
These results raised quite a few eyebrows in the scientific community because people could not believe that collagen would be preserved after many millions of years. Collagen from a second dinosaur—this time, a duck-billed dinosaur from about 80 millions years ago—helped to show that the collagen in T. rex was real. When scientists analyzed the amino acid sequence, they again found that the duck-billed dinosaur was more closely related to the chicken than to any other modern animal.11
If we are starting to find dinosaur collagen in well-preserved fossils, does this mean that Jurassic Park will be a reality in the future? Probably not. Apart from the ethical and practical limitations on bringing dinosaurs back from extinction, it is still scientifically impossible to do this. Collagen is just one of thousands of proteins in the body. It’s an interesting and important piece of the dinosaur biology puzzle, but certainly not enough to build a whole amusement, or terror, park.