Fossilized footprints, preserved in gypsum mud that hardened over time, are estimated to be 23,000-21,000 years old. NPS / Alamy Ancient human footprints, preserved in a dry lakebed at White Sands ...

Live updates, video and analysis from Alexandra Palace as Luke Littler goes back to back at the World Darts Championship against Gian van Veen; watch live on Sky Sports' dedicated darts channel ...