Scientists have found the first dinosaur blood from a bone that was buried for 80 million years. Or, more accurately, they have found a mixture of protein and microstructures that resembles cells. The proteins, taken from the leg bone of a plant-eating hadrosaur, were extensively tested and sequenced by three independent labs to verify the results. Mary Schweitzer of North Carolina State University made a similar find previously, but critics questioned whether the samples were handled and processed correctly. She and her colleagues repeated the process with a new sample and more stringent controls, and again found important materials that could give new clues about dinosaur evolution.

The discovery is especially significant because it has long been thought that this type of protein wouldn’t survive the 65 million years since dinosaurs went extinct. The particular materials recovered from the sample are more durable than DNA and may convey some new information about how and why dinosaurs evolved the way they did. We’re not quite headed toward Jurassic Park, but we may some day be able to trace the evolutionary track that these prehistoric monsters took.