Scientists have spotted cellular structures—and a substance that behaves like DNA—in cartilage more than 70 million years old. But how long can that biological information survive? Inside the tiny fossils, researchers can see what appear to be cells, some frozen in the process of dividing. Others contain darkened balls that look just like nuclei, the cellular structures that store DNA. And one cell even seems to contain dark, tangled coils that resemble chromosomes, the condensed strands of proteins and DNA that form during cell division.
To test the fossilized material, the researchers applied stains that bind to DNA in living cells to the bits of dinosaur skull. These stains stuck to particular spots within the fossil cells, making them glow in fluorescent red and blue.
Does the discovery mean we can sequence dino DNA? Not even close. One recent study even found biomolecules in a fossil of Dickinsonia , a creature that lived over half a billion years ago, and used them to confirm that the organism was an animal rather than another form of life.
The slides with these little bits of dinosaur skull sat in obscurity for over two decades at the Museum of the Rockies until Bailleul—then a Ph. The circular structures looked like cells, and Bailleul noticed that many of them had smaller, darker spots within them, resembling nuclei. Some even contained tangled coils that reminded Bailleul of chromosomes.
Schweitzer, a pioneer in molecular paleontology, had previously published evidence that dinosaur fossils could preserve cells and—controversially—even traces of their original proteins. Schweitzer looked at the fossils and agreed that Bailleul had found something extraordinary. For the next decade, Bailleul worked with Horner, Schweitzer, and their colleagues to study the fossils, treating the endeavor as a long-term side project. In , the team got an unexpected confidence boost when a Swedish group announced that it had found a million-year-old fern with fossilized nuclei and chromosomes.
This nearly whole, deep-black skull belongs to the most complete specimen of Tyrannosaurus rex on display in Europe, an individual nicknamed Tristan Otto. First, the researchers applied chemical stains to the fossils that bind to cartilage, which suggested that the developing bits of dinosaur skull had not yet hardened into bone when the animals died, as the team suspected. Bailleul and Schweitzer then isolated some of the fossil cells and applied propidium iodide and DAPI, two chemical stains widely used in medical research to visualize fresh DNA.
Unsurprisingly, the emu cells better attracted the stains—but the stains also glommed on to specific points within the fossilized dinosaur cells. Past studies have found that genetic material disintegrates in bones after a few million years. Bones are highly porous in life, which makes them imperfect time capsules in death.
Think of DNA as molecules that carry the genetic code , a set of instructions that helps bodies and minds grow and thrive. It determines many of the characteristics that define you, like the color of your eyes or whether your hair is straight or curly. They either decomposed or were eaten by another dinosaur. Made from fossils: The skeleton of a T. We find dinosaur fossils in the ground, in riverbeds and lakes, and on the sides of cliffs and mountains.
Every now and then, someone finds one in their backyard. With enough fossils, scientists can build a dinosaur skeleton — what you see when you go to the museum. A fossil of Parasaurolophus , a dinosaur that lived during the Cretaceous period in what is now North America.
DNA molecules eventually decay. Recent studies show DNA deteriorates and ultimately disintegrates after about 7 million years. That sounds like a long time, but the last dinosaur died at the end of the Cretaceous Period. They discovered DNA fragments in the fossils of Neanderthals and other ancient mammals, such as woolly mammoths. Now that makes sense; those fragments are less than 2 million years old, well before all of the DNA would decay.
Rex watching as an asteroid strikes the Earth, 65 million years ago. The asteroid crash caused an extinction event that killed the dinosaurs.
And where are they left wanting? We discussed this on Orbital , the Gadgets podcast. Best Deals of the Day ». Tech News in Hindi. More Technology News in Hindi. Latest Videos. More Videos.
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