Ah, that classic question on everyone's lips ever since Jurassic Park first appeared in movie theatres in 1993. Is it possible to recreate dinosaurs? Can we clone them? Will we (and should we) ever have an amusement park filled with prehistoric creatures? Well, let's get those questions answered shall we? The possibility might actually surprise you...
What is a clone?
The main way people usually think that (non-avian) dinosaurs can be recreated is via the same way that is used in Jurassic Park, which is through cloning. Cloning is a concept that was long reserved for science fiction, but it was soon cited as a possible reality during the 80s. When scientists first said it was something they were working on, imaginations soon ran wild with the possibilities that this would bring, both good and bad. One science enthusiast and author who ran with this idea was Michael Crichton who then wrote Jurassic Park in 1990, a story, not about dinosaurs, but instead about the hubris of mankind playing with powers they really shouldn't, with dinosaurs simply being the theme for such a moral.
Of course, we all know how successful this story would become, but it also seemed all the more real when, in 1997, humanity saw its very first successfully cloned animal, known as Dolly the sheep. Created by infusing sheep donor cells into an egg with the nucleic DNA removed and using a surrogate mother to grow the lamb, Dolly became world famous as the very first real life clone. This and artificial insemination methods that had already been developed painted a virtually limitless picture.
As many people know these days, cloning requires one vital ingredient: DNA. Deoxyribonucleic acid is the part of any organism that tells each cell in the body what to become (hence why damage to the DNA from something like radiation can cause incorrect cells to grow, also known as cancer). The DNA of every single organism in reality is different, meaning that any natural organism is unlike any other. Now you know how special you are.
This means that a clone is an organism that is an exact copy of another thanks to the fact that the DNA has been sampled from the original.
So what does this mean for dinosaurs?
Well, it's simple to clone a dinosaur, right? All you need is some DNA. Sure it's a little harder to come by, but we can find it in things like preserved samples in amber just like in Jurassic Park... right?...
Wrong.
Jurassic Park did at least ground itself with a few true facts. They were unable to extract DNA from fossilised bones since they are technically no longer bones (hence no more DNA) and the DNA they were able to extract were from blood samples from mosquitos trapped in amber (fossilised tree sap). Even this DNA, however, wasn't perfect, since it had degraded over the years, meaning they had to use frog DNA to fill in the gaps.
Even so, Jurassic Park made DNA out to be a lot more robust than it actually is. Considering how easily damaged DNA can be (again think back to how many relatively minor things can increase cancer risk), think how millions of years of exposure to elements, radiation and geological processes will break it down when it isn't attached to a living organism to sustain itself.
Certain processes are much kinder to DNA, such as mummification, freezing or the aforementioned petrified sap. Even under these rare conditions, however, DNA simply cannot last longer than around 30,000 years (around the same time it takes for the fossilisation process to complete). This is why a mammoth can be cloned (something scientists are now working towards, for better or worse) but a T.rex can't. Mammoths went extinct in around 1650 BCE (only around 3600 years ago), so many remains found are only about 10-15% of the way towards being DNA-less. Remember that non-avian dinosaurs went extinct 66 million years ago, so any DNA they had went away long before we were even around.
As a rule of thumb, if it's a fossil, it can't be cloned. So now, we cannot recreate dinosaurs via cloning.
Some hope for movie and science fans alike...
Don't get too down in the dumps though. This doesn't mean that recreating non-avian dinosaurs is completely out of reach, we just need to rethink how to go about it. Advancements in genetic manipulation have come along in ways other than just cloning. These advancements have revolved mostly around developing ways to combat certain disorders and diseases, but once it has been mastered, the possibilities are hypothetically endless.
Rather than looking at recreating DNA, we should look instead into rewriting it. Manipulating the DNA of an existing animal means that it can grow into whatever form we like, within reason (if the animal is similar enough to the form we are trying to create). The only possible way of getting close to an extinct animal that has been dead too long to clone is to find its closest living relative, then manipulate the DNA enough from a sample so that the embryo grows how we want it to. So if we want to create a dinosaur, why not use...well...a dinosaur?
If you've followed this blog for a while, you're probably sick of me saying this, but dinosaurs are still very much alive and they are the things that wake you up every morning and crap on your car. Also known as avian dinosaurs, birds are scientifically classed within the group of Dinosauria, specifically theropoda (the two-legged dinosaurs). Whilst it seems somewhat mind-bending to think that a crocodile (which belongs in the same group as dinosaurs known as archosauria) has more relation to a penguin than it does to a monitor lizard, it does make sense when we break down features of a birds skeleton (something I have done in this post).
All you really have to do to a bird to make it (superficially) a non-avian dinosaur is to make its tail longer, replace the beak with a snout with teeth and separate the fingers in its fused wings. If you can do that, changing the DNA to make it grow bigger, grow horns, grow a longer neck or grow back plates shouldn't prove much more of a difficulty.
Of course, this does mean that any animal created is definitely not a dinosaur that has ever existed, let alone a clone from the Mesozoic. Remember though, the Jurassic Park/World films have stated several times that the movie monsters we see are NOT exact copies of what once naturally walked the Earth, rather designed creatures meant to entertain and inspire awe (likely to placate paleo-nerds like me without having to change their creature designs to suit science), so even if Jurassic Park could be made in real life, we would not be seeing the actual dinosaurs that walked the Earth.
Whilst it's amazing that dinosaurs have captured the imagination of and inspired countless people, we must remember that we are not talking about movie monsters, we are talking about animals.
But bringing it back to cloning, I mentioned earlier that scientists are potentially working towards cloning a woolly mammoth. The question is...should they?
Sure, such a breakthrough in biology would mean astounding things for healthcare and quality of life overall for humankind, but what actual need do we have to justify having woolly mammoths living among us? For entertainment? I have my own opinion on the matter but, ultimately, I'll let you decide.
Until next time!
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