The cartilage, from the Hypacrosaurus species of the Cretaceous Period , is over 70 million years old but has been calcified and fossilized, which may have protected the inside of the cells. So, will it ever be possible to bring a dinosaur back from extinction? It's something that scientists are trying to work out, although the process would be quite different to how it's portrayed in the movies. We can get collagen and some dinosaur proteins, but not all the material we need," paleontologist Jack Horner told How It Works magazine.
The thing to do would be to grow it in a test tube, because we have no idea how big the embryos of all dinosaurs are. Some dinosaur eggs are the size of ostrich eggs, but for a Tyrannosaur, we think they are a lot longer and they're bigger. It's like thinking about putting a human embryo inside a squirrel. Horner is the real paleontologist who inspired the character of Alan Grant in "Jurassic Park.
He was also the palaeontology consultant for the "Jurassic Park" films. And while he deems the cloning process pure fiction, it hasn't stopped Horner from trying to bring back the dinosaurs. The idea is to use atavistic genes. They are basically ancestral genes, meaning that ancestral animals programmed certain features.
For instance, occasionally children are born with extra vertebrae and form a low tail, which the doctor just picks off when the child is born. And every once in a while snakes are born with little appendages.
Horner's plan is to take advantage of these atavistic genes. All bird species are related to one another, with one common ancestor — dinosaurs — so any bird should work. Chickens are the easiest thing to get eggs from, so I built a laboratory, hired some geneticists and developmental biologists and started seeing if we could find some of these potential atavistic genes," he said. We are trying to figure out how the tail actually works and reverse the process that formed the short tail.
So, are we any closer to making a dinosaur? I think we can do pretty much all the rest of the body. We have the potential of making an animal that has a dinosaur-like head, probably with teeth in it, and we certainly have the capability of reversing the wings to make arms and hands. We know we can do that, but right now we're just trying to fix the tail," Horner said.
If humans did succeed in bringing dinosaurs back from extinction, how would we coexist? If dinosaurs hadn't gone extinct, humans are unlikely to have been able to evolve. But there is one other potential avenue to consider when bringing back dinosaurs—the fact that they are still here, except we call them birds. As Julia Clarke, a paleontologist and professor with the Department of Geological Sciences at the University of Texas at Austin, told Live Science in "Birds are living dinosaurs, just as we are mammals… All of the species of birds we have today are descendants of one lineage of dinosaur: the theropod dinosaurs.
The average pigeon is not what most people will imagine when asked to bring to mind a dinosaur, but this bird-dinosaur lineage does present the idea that dinosaur-like traits could be reverse-engineered out of birds.
For Maidment, this possibility is not compelling. She said: "So there's kind of this idea that you can tweak their genome to express or not express various genes that might make them more like dinosaurs… but that doesn't give you a dinosaur.
In any case, bringing back dinosaurs does present a number of ethical qualms, Maidment adds, who questions who would own them, what rights they would have, and where they would fit into the ecosystem. Using the stegosaurus as an example, she said: "The plants that they fed on went extinct hundreds of millions of years ago. There's this whole ethical thing around it that I think is much less talked about, but much more of a concern. But when amber preserves things, it tends to preserve the husk, not the soft tissues.
So you don't get blood preserved inside mosquitos in amber. This Lebanese amber specimen dates back to the Early Cretaceous Period. It is around million years old. This means that Jurassic Park is probably not possible exactly as Michael Crichton wrote it. But the search for dinosaur DNA doesn't end there. Blood residue has been found inside ancient insects - they just weren't found in amber.
The mosquito was preserved in lake sediments and had a red pigment in its abdomen. When they tested that pigment chemically they discovered haemoglobin-derived porphyrins. These are the breakdown products of haemoglobin, which is the red protein that carries oxygen around the body in the blood of almost all vertebrates. When under specific circumstances blood does preserve, it doesn't mean that scientists will find DNA in it.
So even if a dinosaur's blood was found inside an ancient insect, an opportunity to recreate the reptile from it isn't guaranteed.
In , Susie and her colleagues discovered what they interpreted to be red blood cells inside a Cretaceous dinosaur fossil bone. The blood cells have nuclei and you don't find those in mammals, so it must be a reptilian red blood cell. We compared it with red blood cells from birds and it showed some morphological similarities.
Albertosaurus is a dinosaur that lived during the Late Cretaceous Period. Scientists may one day find blood or soft tissues in the fossils of these animals, which are around 70 million years old. Ancient DNA has so far been recovered from permafrost, as well as from subfossils - bones or body parts that have not yet fossilised. But DNA is vulnerable and breaks down rapidly.
Sunlight has negative effects and water can also accelerate deterioration. Modern contamination is also a problem. DNA has to be handled under strictly controlled conditions. Currently the oldest DNA to have been found is around one million years old, although it is possibly younger.
DNA 66 times older would have to be found to get to the age of dinosaurs. If dinosaur DNA were found, what happens next? If you work at Jurassic Park's genetic engineering facility you simply combine it with frog DNA and recreate an extinct reptile.
They identified where the holes are and filled them with frog DNA. But the problem is that you don't know where the holes are if you don't have the whole genome,' explains Susie.
A genome is the complete set of DNA of a living thing. Without the full genome, it would be impossible to tell which parts of the DNA have been found and therefore impossible to fill the gaps to build a whole animal.
If you were going to do it, you'd use bird DNA, because birds are dinosaurs. Or you might do it with crocodile DNA, because they share a common ancestor. DNA breaks down over time.
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