Evidence of absence: “Interpreting fossils that aren’t there comes with its own peculiar challenges, and these gaps and ghosts that haunt the fossil record are a big part of palaeontology’s allure. In dinosaur palaeontology, sample sizes are often small, and the challenge is to find creative ways to extract information from fossils. One of the most daring moves of all is to begin treating the fossils we don’t have as data.”