Dinosaurs, DNA and Jurassic World: Fallen Kingdom


Full disclosure: Hollywood is not going to make money off my two or three movies a year attendance.  But when I do go to the cinema I want to be entertained with action adventure movies.  I grew up on movies like The Vikings. [And what was Janet Leigh thinking, preferring pasty faced Tony Curtis over that hunk, Kirk Douglas?]   John Wayne is my hero and I am still waiting for Frank Sinatra to finally make that damn train in Von Ryan’s Express!   
With this history (Jennifer Aniston, take note, there is not a romantic comedy on that list) you might guess that I like the Jurassic Park franchise.  Correct!  I will attend Jurassic World: Fallen Kingdom when it opens this month and I will not be alone.  We all like dinosaurs.  They have it all: remarkable size, distinctive features, mystique and—best of all—they are dead.  Dinosaurs, unlike personalities or ideologies, are a piece of history that can not come back to threaten us. 
Or can they?
Ever since Michael Crichton published his novel, Jurassic Park, in 1990, people have been fascinated with the thought of using pre-historic DNA to bring dinosaurs back to life.  We have intact DNA from both Neanderthals and woolly mammoths.  So why not capture some of that DNA from dino-blood encapsulated in mosquitoes caught in amber?  The concept is intriguing, and an excellent fictional premise.  Crichton gets full marks for this gambit.  But, there is a deadly flaw.  Time.
The oldest known DNA is about a million years old.  To go back to DNA from dinosaurs we must back track at least another 66 million years.  The DNA in those mosquitoes is simply too degraded to be useful.  A single snip of DNA does not a dinosaur make.    
We do know the overall genomic structure of dinosaurs.  But that does not mean we know the DNA structure of specific animals (T-rex, for example).  Dinosaurs emerged about 240 million years ago.  They first show up in the Mesozoic era, which is divided into three periods (from oldest to youngest) the Triassic, Jurassic and Cretaceous.  That is much older than the intact DNA from woolly mammoths and Neanderthals that occur in the Pleistocene and Holocene periods of the Cenozoic era respectively.  To let you know just how recent that is, keep in mind that we live in the Holocene period ourselves.   
But even if we had a reasonable amount of dino-DNA, that still doesn’t equal a dinosaur.  Filling in the gaps in fragmented DNA with frog (or better still, bird)  DNA does not produce a dinosaur any more than a bird or a frog.
What is more, if you put this altered DNA into a non-dinosaur egg you have a further misalignment of events.  A strand of DNA does not spontaneously grow into its assigned creature.  There is a cascade of chemical interactions that cause certain genes to switch on and off at exactly the right time to trigger the creation of our little triceratops.  These chemical switches are unique to each egg.  People have tried putting chicken DNA into an ostrich egg to see what comes out.  The answer is nothing.  The magic of ostrich eggs only works for ostriches.  Chicken DNA dies in those eggs.  You may or may not be able to put woolly mammoth DNA into an elephant egg, but dinosaur DNA in any Cenozoic egg is an incredible stretch. 
If you really want to see living dinosaurs, look at the birds.  They are the remnants of the last great extinction of the dinosaurs at the end of the Mesozoic. If you want to create your own velociraptor—well—it isn’t going to happen any time soon.   
Life is a knowable and understandable miracle, but it is still a miracle.  Keep the faith.  

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