Dinosaurs

And very much still relevant 30 years later More on reddit.com

It depends on the dinosaur. DNA breaks down completely over just a couple of million years, and it’s completely useless after after a few thousand (it can vary based on climate). Any dinosaur that went extinct within the past few hundred or thousand years could possibly be brought back. Something like Raphus cucullatus is probably one of the least controversial and species to resurrect and has had some of the most research put into it. I’m guessing you actually mean non-avian dinosaur. The answer to that is definitely not. Jack Horner has tried and failed. He was claiming it can help to teach about evolution, but really he just wanted to eat it. The project involved reactivating dormant genes in a chicken to give it teeth, scales, hands and a tail. The genes to create a long tail don’t exist in chickens so he tried creating a chimera using a crocodile’s tail genes. Technically the project is still ongoing but everyone in palaeontology criticises it and progress has basically stopped altogether. The DNA of non-avian dinosaurs is gone, there are no close enough relatives to serve as surrogate mothers and you can’t turn one species into another with gene editing. This is a complete fantasy and waste of scientific funding. More on reddit.com

They didn't look the way most people envision them at all, because most dino art up until very recently treated them as if they were just skin stretched tightly over skeletons with very little muscle or fat. Animals simply don't look that way. They were likely chubbier and fluffier than what we envision, especially around the face, and that's not to mention the feathers and plausible bright coloration. More on reddit.com

Most of your favorite dinosaurs didn’t live a the same time. They were mostly spread across 200 million years or so, and across the entire globe. Notable exceptions: allosaurus and stegosaurus lived together, as well as Tyrannosaurus rex and triceratops did. More on reddit.com