Stock Photo: Barstow, California - The Calico Early Man Archeological Site Items resembling stone tools recovered from the site date to 200,000 years ago, scientists do not agree on whether they were made by early man or by natural geological processes A sign points. Barstow, California - The Calico Early Man Archeological Site Items resembling stone tools recovered from the site date to 200,000 years ago, scientists do not agree on whether they were made by early man or by natural geological processes A