Can We Clone a Dinosaur?

The Hard Facts, and Entertaining Fiction, of Dinosaur Cloning

The Tyrannosaurus Rex skeleton known as Sue stands on display at Union Station in Washington D.C.
Tyrannosaurus Rex skeleton on display in 2000 at Union Station in Washington D.C. Mark Wilson/Hulton Archive/Getty Images

A few years ago, you may have come across a realistic-looking news story on the web: headlined "British Scientists Clone Dinosaur," it discusses "a baby Apatosaurus nicknamed Spot" that was supposedly incubated at the John Moore University College of Veterinary Medicine, in Liverpool. What made the story so unnerving was the realistic-looking "photograph" of a baby sauropod that accompanied it, which looked a bit like the creepy baby in David Lynch's classic film Eraserhead.

Needless to say, this "news item" was a complete hoax, albeit a very entertaining one.

The original Jurassic Park made it all look so easy: in a remote laboratory, a team of scientists extracts DNA from the guts of hundred-million-year-old mosquitoes petrified in amber (the idea being that these pesky bugs, of course, feasted on dinosaur blood before they died). The dinosaur DNA is combined with frog DNA (an odd choice, considering that frogs are amphibians rather than reptiles), and then, by some mysterious process that's presumably too difficult for the average moviegoer to follow, the result is a living, breathing, completely inaccurately portrayed Dilophosaurus straight out of the Jurassic period.

In real life, though, cloning a dinosaur would be a much, much more difficult undertaking. That hasn't prevented an eccentric Australian billionaire, Clive Palmer, from recently announcing his plans to clone dinosaurs for a real-life, down-under Jurassic Park.

(One presumes that Palmer made his announcement in the same spirit that Donald Trump initially tested the waters for his presidential bid--as a way of attracting attention and headlines.) Is Palmer one shrimp short of a full barbie, or has he somehow mastered the scientific challenge of dinosaur cloning?

Let's take a closer look at what's involved.

How to Clone a Dinosaur, Step #1: Obtain a Dinosaur Genome

DNA--the molecule that encodes all of an organism's genetic information--has a notoriously complex, and easily breakable, structure consisting of millions of "base pairs" strung together in a specific sequence. The fact is that it's extremely difficult to extract a full strand of intact DNA even from a 10,000-year-old Woolly Mammoth frozen in permafrost; imagine what the odds are for a dinosaur, even an extremely well-fossilized one, that has been encased in sediment for over 65 million years! Jurassic Park had the right idea, DNA-extraction-wise; the trouble is that dinosaur DNA would completely degrade, even in the relatively isolated confines of a mosquito's fossilized tummy, over geologic stretches of time.

The best we can reasonably hope for--and even that's a long shot--is to recover scattered and incomplete fragments of a particular dinosaur's DNA, accounting for perhaps one or two percent of its entire genome. Then, the hand-waving argument goes, we might be able to reconstruct these DNA fragments by splicing in strands of genetic code obtained from the modern descendants of dinosaurs, the birds.

But which species of bird? How much of its DNA? And, without having any idea what a complete Diplodocus genome looks like, how would we know where to insert the dinosaur DNA remnants?

How to Clone a Dinosaur, Step #2: Find a Suitable Host

Ready for more disappointment? An intact dinosaur genome, even if one were ever miraculously to be discovered or engineered, wouldn't be sufficient, by itself, to clone a living, breathing dinosaur. You can't just inject the DNA into, say, an unfertilized chicken egg, then sit back and wait for your Apatosaurus to hatch. The fact is that most vertebrates need to gestate in an extremely specific biological environment, and, at least for a short period of time, in a living body (even a fertilized chicken egg spends a day or two in the mother hen's oviduct before it's laid).

So what would be the ideal "foster mom" for a cloned dinosaur? Clearly, if we're talking about a genus on the larger end of the spectrum, we'll need a correspondingly hefty bird, if only because most dinosaur eggs were significantly bigger than most chicken eggs. (That's another reason you couldn't hatch a baby Apatosaurus out of a chicken egg; it's just not capacious enough.) An ostrich might fit the bill, but we're so far out on a speculative limb now that we might as well just consider cloning a giant, extinct bird like Gastornis or Argentavis! (Which may yet be barely possible, given the controversial scientific program known as de-extinction.)

How to Clone a Dinosaur, Step 3: Cross Your Fingers (or Claws)

Let's put the odds of successfully cloning a dinosaur into perspective. Consider the common practice of artificial gestation involving human beings--i.e., in vitro fertilization. No cloning or manipulation of genetic material is involved, just introducing a bunch of sperm to an individual egg, cultivating the resulting zygote in a test-tube for a couple of days, and implanting the embryo-in-waiting into the mother's uterus. Even this technique fails more often than it succeeds; most times, the zygote simply doesn't "take," and even the smallest genetic abnormality will cause a natural termination of the pregnancy weeks, or months, after implantation.

Compared to IVF, cloning a dinosaur is almost infinitely more complicated. We simply don't have access to the proper environment in which a dinosaur embryo can gestate, or the means to tease out all the information encoded in dinosaur DNA, in the proper sequence and with the proper timing. Even if we miraculously got as far as implanting a complete dinosaur genome into an ostrich egg, the embryo would, in the vast majority of cases, simply fail to develop. Long story short: pending some major advancements in science, there's no need to book a trip to Australia's Jurassic Park! (On a more positive note, we're much closer to cloning a Woolly Mammoth, if that will in any way fulfill your Jurassic Park-inspired dreams.)