I found this bone in the sea cliff at Poplar Beach in Half Moon Bay, California. I found the bone partially sticking out of the cliff about 30 ft below the top of the cliff facing the ocean. A reputable marine biologist, Dr Bob Rubin, identified the bone as being the head of humerus from an extinct whale species known as Cetother. This whale species went extinct about 10,000 years ago and is related to the Grey Whale.