And whether we'll be able to build a dinosaur one day.
In Jurassic Park, dinosaurs were brought back to life after scientists grabbed their DNA from a bug encased in amber. Not a bad idea, but in real life, 66-million-year-old DNA would be way too degraded to be of much use, says Hans Larsson, a paleontologist at McGill University. "Maybe there is a way, but we haven't found it yet."
Larsson and a few other scientists are trying a different approach to bringing back the dinosaur: resurrecting the long-extinct animal's traits in a living ancestor, the chicken. It's an idea that's been popularized by paleontologist Jack Horner (the real-life inspiration for Alan Grant in Jurassic Park), who frequently talks about his wish to make a "Chickenosaurus." We might just be getting closer. In a new experiment, scientists in Chile say they've managed to grow dinosaur-like legs on a chicken.
Just about everybody, scientists included, has fantasized about bringing the dinosaurs back
Bird embryos start out early in their development looking more like dinosaurs, with a fibula bone in the leg that reaches down to the ankle, and matches the tibia. In grown-up birds, it's splinter-like and shorter than the tibia. By shutting off a bone maturation gene called Indian Hedgehog (scientists give all sorts of bizarre names to the genes they discover), the Chilean team coaxed the bird to grow a dinosaur-like fibula.
It's the second time that Joâo Botelho, author of the new study, has published work like this like this. Last year, he produced a bird embryo with a non-opposable toe, like a dinosaur. Another team, from Yale University, made a chicken embryo with a dinosaur-like snout, something similar to what small dinosaurs like Velociraptor would have had.
Larsson, who holds the Canada Research Chair in Vertebrate Paleontology, is doing similar work in his Montreal lab (when he's not out digging for dino bones). "It's progressing really well," he said. The first step is understanding "basic developmental biology," and what's actually going on inside the chicken embryo as it matures. Once that part is solved, the researchers can "go back in time" to find switchpoints that lead to other types of anatomy—including that of a dinosaur. "We're really trying to understand how dinosaurs evolved."
Just about everybody, scientists included, has fantasized about bringing the dinosaurs back. Making the Chickenosaurus that Horner envisioned "could be the end goal," Larsson mused, but all that's still an extraordinarily long way off. The Chilean scientists, for one, say that's not what they're after, and the researchers from Yale emphasized the same. All these scientists are trying to better understand how birds evolved from dinosaurs, but to Larsson, a living Chickenosaurus would be a perfect illustration of that come to life.
"It would take huge amounts of experimentation" to understand all the changes necessary to make a dinosaur, he said, and trying it all at once in a chicken embryo "would be like doing open-heart surgery, times one thousand." But with powerful new gene editing tools like CRISPR-cas9, it doesn't sound so impossible anymore.