Assuming this is 1999, convert these ages into BP dates. Example: an article 1000 years old has a BP age of 951. [BP = Age - (Today -1950) = 1000-(1999-1950) = 951] Age BP Date 7.Wood from Bristlecone Pine of White Mountains, California. Age 4731 ± 75 years 8.Pleistocene mammoth bone from La Brea Tar Pits of Los Angeles, California. Age: 12,200 ± 35 years.Cottage roof timber from Ireland. Age: 906 ± 35 years