NASA's Mars Curiosity Rover has recently discovered what some conspiracy theorists believe to be an animal “thigh bone” on the red planet's surface, a report by The Independent said. An image taken by the Rover’s MastCam on August 14 appears to show a thigh bone that probably belongs to animals, possibly dinosaurs. For space news enthusiasts, the spotted “alien thigh bone” can be a “proof that large animals once roamed Mars,” the newspaper added. The odd object can hint that some complex life forms may have existed on Mars during a time in history. NASA’s Curiosity Rover has recently completed its second year exploring Mars, where it has been investigating the climate and geology of the red planet.