Sixty-six million years ago, the last of the dinosaurs died off, bringing an end to the 140-million-year dominance that this fascinating group of reptiles enjoyed.
We only started learning about these animals in the 1800s.
But since the first dinosaur fossil was discovered, scientists have had numerous questions about them, like what they looked like, how they lived, and why they went extinct.
Thanks to decades of painstaking scientific work, we now have answers to some of these questions.
One of the big questions that remain to this day is whether or not we could actually bring them back.
For instance, scientists can now make precise changes to DNA using gene editing tools like CRISPR-Cas9.
This and other recent advancements in science and technology have been pushing the boundaries of what was once considered science fiction, bringing us closer to the possibility of resurrecting dinosaurs and ancient creatures.
But how plausible is this idea, and how close are we to seeing it happen?
In this article, we’ll explore the concept of bringing dinosaurs back to life, how it might be achieved, and the challenges that impede that possibility.
The Dinosaurs That Once Ruled
Between 252 and 66 million years ago, dinosaurs were the most dominant land animals.
They evolved from archosaurs during the Triassic Period.
The diversification of the dinosaurs, which allowed them to become the most dominant group of land animals, began towards the end of the Triassic.
But the height of their dominance was the Jurassic, during which they radiated into multiple species and occupied various ecological niches.
Saurischians, or lizard-hipped dinosaurs, were the most successful group.
The group includes theropods (bipedal carnivores like the famous T. rex and Velociraptor) and sauropods (a group that includes some of the largest dinosaurs ever discovered, like the Diplodocus and Argentinosaurus).
Theropods were the apex predators of the Mesozoic Era on various continents, while the sauropods were top consumers.
Ornithischians are also known as lizard-hipped dinosaurs, and they were all herbivores.
The major groups of dinosaurs within this family include the stegosaurs, ankylosaurs, ceratopsians, and ornithopods.
The factors that favored the dominance of the dinosaurs include their upright posture, varied diet, large size, and possibly the warm-blooded nature of some of them, which allowed adaptation to different environments.
The dominance of the dinosaurs continued well into the Cretaceous Period.
While many species went extinct at various points during the Mesozoic as a result of local factors, several new species emerged as well.
The total extinction of the dinosaurs is one of the great mysteries of paleontology, mainly because of how sudden it was.
Although there’s a remote possibility that their extinction happened slowly over the course of several million years, the fact that they disappeared from the fossil record so abruptly suggests otherwise.
Experts think a major catastrophic event on a global scale took out the majority of the dinosaurs within a short time.
An asteroid impact, volcanic eruptions, and sudden climate change are likely culprits.
A combination of all of these factors may have caused a collapse of the Cretaceous ecosystem, leading to the starvation and death of the few surviving dinosaurs.
Jurassic Park and the Resurrection Dream
The depiction of dinosaurs in movies dates as far back as 1914.
By the time Steven Speilberg’s movie adaptation of the Jurassic Park novel was released in 1993, several other dinosaur-themed movies had been produced.
What set Jurassic Park apart from all the other previous films was the use of CGI to portray dinosaurs on the big screen for the first time.
This movie did a good job of reawakening a frenzied fascination with these prehistoric beasts.
Jurassic Park also teased the idea of bringing dinosaurs back using science.
The movie was based on a simple but almost completely fictional premise.
In Jurassic Park, scientists discovered a method for bringing back dinosaurs using DNA recovered from mosquitoes preserved in amber.
Since DNA contains all the genetic information for the appearance, growth, and function of a living thing, this preserved DNA was used as a blueprint for recreating the dinosaurs.
The partial DNA was then combined with the DNA of living animals like amphibians and reptiles to create a dinosaur.
Separating Facts From Fiction
The ingenuity of the novel’s author is in using a scientifically plausible plot.
But even if cloning dinosaurs this way could theoretically work, the major ingredient needed to make this happen in reality is dinosaur DNA, which is almost impossible to get.
Mosquitos and other biting insects were alive during the time of dinosaurs, and many of them were preserved in amber.
However, insects preserved in amber cannot retain soft tissues like blood.
Only hard parts are preserved this way, which makes Jurassic Park’s mode of preservation unlikely—strike one for the movie.
But it is possible to obtain dinosaur blood from insect fossils preserved in some other ways.
For instance, scientists once found a mosquito fossil from the Eocene Epoch (45 million years ago) with some blood cells preserved.
The fossil, in this case, was preserved in lake sediments.
The Eocene was 20 million years before the dinosaurs went extinct, meaning the chances of finding a fossil like this are very low.
Even worse, the blood tissue found in the 45 million-year-old blood contained no DNA material.
The oldest DNA found so far is from a fossil dating back to about one million years ago.
The Brachylophosaurus, for example, was found with fragmentary DNA in its fossils.
So, if we ever find dinosaur blood preserved inside an ancient insect or any other type of dinosaur tissue, the chances of cloning a dinosaur from it are very slim.
Let’s assume by a stroke of luck, we somehow obtain dinosaur DNA; how exactly do we clone a complete animal from it?
In the movie, genetic engineering was used to combine the incomplete dinosaur DNA with frog DNA.
Basically, the idea is to fill the holes in the fragmented DNA with the DNA of living animals.
We’ll have to reconstruct the dinosaur’s full genome (complete set of DNA) to make a complete animal fully identical to dinosaurs.
However, because we don’t have a full dinosaur genome to use as a comparison, it will be impossible to determine what parts of the DNA are missing and what parts we have.
Also, the movie used amphibian and reptilian DNA to create the dinosaurs, even though the closest living relatives to dinosaurs are birds or crocodiles.
Despite these scientific plot holes, the seeming plausibility of cloning dinosaurs from ancient DNA, as presented in the Jurassic Park novel and movie, managed to spark serious conversation in the scientific world about bringing back dinosaurs.
The Science Behind De-Extinction
But beyond fiction, can we really bring back dinosaurs somehow? The truth is, there’s a chance we can.
Recovering ancient DNA from mosquitoes, as depicted in “Jurassic Park,” is very unlikely due to the challenges associated with ancient DNA preservation.
But there are other more likely methods we can explore, thanks to modern advancements in genetic engineering and DNA extraction.
To revive an extinct species, we need intact DNA from the animal.
Obtaining dinosaur DNA remains challenging because of degradation over millions of years.
However, recent advances in DNA extraction techniques have improved the chances of success.
In 2015, a team of scientists recovered red blood cells from Cretaceous dinosaur fossil bones.
Using the technology available at the time, they could not obtain any DNA from this blood cell.
But advancements in technology or the discovery of better-preserved fossils (preferably mummified remains entombed in ice) may one day allow this.
Suppose scientists are ever able to obtain a viable somatic cell from a dinosaur.
In that case, they can extract a nucleus from this cell and insert it into an egg cell of a closely related species (probably birds).
This reconstructed egg is stimulated to develop into an embryo, which can be incubated or implanted into a surrogate mother for gestation.
But the more plausible way we could revive dinosaurs is through genetic engineering.
Instead of looking for the DNA of an animal that died 66 million years ago, we can simply obtain the DNA from a living dinosaur (think birds!).
Thanks to modern genetic mapping and engineering techniques, scientists may be able to find the variations between dinosaur and bird DNA and reverse these variations.
Going from chicken to tyrannosaur would mean reversing 66 million years of evolution.
Challenges and Ethical Concerns
The de-extinction of dinosaurs remains a challenging and complex field for now.
But from the current technological trends, the bigger question in the coming years may not be whether or not we can bring back dinosaurs.
It’ll be whether or not we should.
Even if we could, bringing ancient animals back comes with some potential ethical and ecological dilemmas:
First, the animal you’ll be creating by reengineering a bird’s DNA or combining a dinosaur’s DNA with that of any other living animal would technically not be a dinosaur.
It might be similar to dinosaurs, but it won’t be a dinosaur on a molecular level.
In turning time back by 66 million years, there’s no telling where you’ll end up.
Without a complete dinosaur genome to compare to, there’s no way to determine if the animal we’ll be cloning is really a dinosaur.
Another fundamental ethical question is whether humans should act as creators of life, effectively “playing God.”
Some argue that tampering with the natural order of extinction and evolution raises moral questions about our responsibility and the consequences of our actions.
We could make a sound argument for bringing back an animal hunted to extinction by humans, like the dodo bird.
But for animals that died off naturally due to extinction, we might be messing with factors well beyond our control if we bring them back.
Throughout geologic history, the Earth’s flora and fauna aren’t the only things that have changed.
The climate has shifted significantly as well.
An animal that was alive 150 million years ago had to live under a completely different climatic condition.
Even the composition of the Earth’s atmosphere and the salinity of the ocean isn’t at the same level that it was during the Mesozoic.
Essentially, a dinosaur will most likely be out of place in today’s world.
Re-creating the original environments that dinosaurs lived in and ensuring they are suitable for these resurrected species will be a daunting task (if possible at all).
If Jurassic Park has taught us anything, it’s the fact that we need to worry about the place of humans in a world of dinosaurs.
Within the past few centuries, human activity has transformed many landscapes, and human-wildlife interactions have evolved.
If we do manage to create an ecological paradise for dinosaurs, there’s a risk of conflict and other issues relating to the coexistence of humans with these resurrected beasts.
But humans are not the only inhabitants of the planet we have to worry about.
The reintroduction of extinct species would entirely disrupt modern ecosystems.
No modern predators can prey on a sauropod or any of the other large herbivores of the Mesozoic.
This means many of these species may have no natural predators or prey unless we somehow manage to create one for them.
From observing present-day ecosystems, we know that introducing foreign invasive species to a new ecosystem can cause imbalances.
For instance, the Burmese python is a species of large python native to Southeast Asia.
It was introduced to Florida in the 90s as a pet, but many of them were released into the wild.
Burmese pythons have since established a breeding population in Florida, and they are now considered a major threat to native wildlife.
The Asian carp is another good example.
This fish is native to Asia but was introduced to the United States in the 1970s.
It is now a major problem to the natural ecosystem of the Great Lakes and other waterways, where they are outcompeting native fish species.
Imbalances like this may be among the unintended consequences of reintroducing ancient animals like dinosaurs into the current ecosystem.
Resurrected animals will also have some trouble adjusting to the present-day ecosystem.
For instance, they may lack immunity to various modern diseases and pathogens.
There’s also no telling how these pathogens will mutate in the body of these new hosts.
It could lead to serious disease mutations that could have devastating effects both on the population of the reintroduced species and on the other animals in their ecosystem.
Success Stories in De-Extinction
Although de-extinction remains controversial, scientists are already working to bring some extinct animals back from the dead.
The Pyrenean ibex, a species of wild goat that once lived in the Pyrenees Mountains, is one of the most notable candidates for de-extinction.
Scientists successfully cloned a female bucardo in 2003 using somatic cell nuclear transfer (SCNT).
Unfortunately, the clone could not survive for long due to defective lungs, dying shortly after birth.
This project highlighted one of the likely challenges of de-extinction: the health issues cloned animals are likely to face.
Despite its ultimate failure, the Pyrenean ibex cloning project did provide scientists with valuable data that may be helpful for future de-extinction projects.
Another example is the Passenger pigeon, a species that was once abundant across North America, with a population of over five billion.
Scientists are now working on bringing back the passenger pigeon by editing the genome of the closely related band-tailed pigeon.
Currently, the DNA code of this species has been sequenced.
The next stage involves determining the section of the genetic code responsible for regulating specific cell functions and creating traits, then modifying these sections.
The passenger pigeon de-extinction project will provide lots of data and insights into bringing back extinct animals using genome editing methods.
Other animals that scientists are currently working on resurrecting this way include the wooly mammoth, thylacine, and aurochs.
Dinosaur Candidates for Resurrection
Even if we could theoretically bring dinosaurs back, we wouldn’t be able to bring all of them back.
Based on current technology, the best candidates for de-extinction are species whose DNA sequence is at least partly known.
So far, no dinosaur DNA has been recovered, but there have been a few dinosaurs with some of their soft tissues preserved.
Some notable fossils, like the mummified nodosaur fossil, were found with significant parts of the soft tissues preserved.
Another factor that will determine which dinosaur to choose is the proximity of living relatives.
The Archaeopteryx is a good candidate in this case, not only because it is closely related to birds but because some soft tissues of this dinosaur have also been found.
In fact, scientists were able to determine the color of this dinosaur by studying the pigment cells.
The oviraptorosaurs are another group closely related to modern birds with soft tissue materials that could potentially yield DNA.
In one instance, scientists found the remains of an oviraptorosaur embryo inside its egg.
The embryo was still curled up in the egg, and its feathers were still attached.
In bringing back dead dinosaurs, scientists also have to consider the potential ecological impact of this species.
For instance, while DNA materials could be potentially recovered from the fossils of Sue the T-rex, bringing back a carnivorous dinosaur might not be a good idea.
The Road Ahead: Can We Really Bring Them Back?
Scientists have made significant strides in improving DNA extraction techniques.
But more than 66 million years have passed since the last dinosaur died.
This makes the recovery of intact dinosaur DNA almost impossible.
Consequently, experts are focusing on more plausible ways of bringing back extinct animals, such as reverse-engineering DNA.
Advancements in genetic engineering tools will make more precise DNA manipulation possible in the future.
Technology like this will prove valuable in future attempts to recreate dinosaur-like traits in related species.
However, there’s still a long way to go regarding our understanding of dinosaur DNA.
We have only recently identified birds as the closest living relatives to dinosaurs.
Going from that to recreating the appearance, behavior, and physiology of dinosaurs in the coming years might be a long stretch.
Dinosaurs are majestic creatures whose existence continues to fascinate us.
This has prompted numerous studies to understand these creatures and possibly bring them back to extinction.
The Jurassic Park novel and movies are reimaginations of a world where dinosaurs coexist with humans.
The science of this and other dinosaur-themed movies is questionable, but bringing back dinosaurs is not entirely implausible.
We might simply need to explore other methods, such as cloning and genetic re-engineering of dinosaur relatives.
Even with the technology, the ethical and ecological challenges of bringing dinosaurs back may also create new problems.
However, the concept of de-extinction is not limited to dinosaurs.
There’s a chance we can potentially revive some recently extinct species and bring some endangered species back from the brink of extinction.
This could contribute to preserving our current biodiversity and restoring ecosystems.
This is arguably more important than resurrecting dinosaurs.