Calaveras Skull

The Calaveras Skull was a human skull found by miners in Calaveras County, California, which was purported to prove that humans, mastodons, and elephants had coexisted in California. It was later revealed to be a hoax. Coincidentally, "calaveras" is the Spanish word for "skulls".

On February 25, 1866, miners claimed to have found a human skull in a mine, beneath a layer of lava, 130 feet (40 m) below the surface of the earth, which made it into the hands of Josiah Whitney, then the State Geologist of California as well as a Professor of Geology at Harvard University. A year before the skull came to his attention, Whitney published the belief that humans, mastodons, and elephants coexisted; the skull served as proof of his convictions. After careful study, he officially announced its discovery at a meeting of the California Academy of Sciences on July 16, 1866, declaring it evidence of the existence of Pliocene age man in North America, which would make it the oldest known record of humans on the continent.

Its authenticity was immediately challenged. In 1869 a San Francisco newspaper reported that a miner had told a minister that the skull was planted as a practical joke. Thomas Wilson of Harvard ran a fluorine analysis on it in 1879 (the first ever usage of such on human bone), with the results indicating it was of recent origin. It was so widely believed to be a hoax that Bret Harte famously wrote a satirical poem called "To the Pliocene Skull" in 1899.

Whitney did not waver in his belief that it was genuine. His successor at Harvard, F. W. Putnam, also believed it to be real. By 1901 Putnam was determined to discover the truth and he headed to California. While there, he heard a story that in 1865 one of a number of Indian skulls had been dug up from a nearby burial site and planted in the mine specifically for miners to find. Putnam still declined to declare the skull a fake, instead conceding, "It may be impossible ever to determine to the satisfaction of the archaeologist the place where the skull was actually found." Others, such as adherents of Theosophy, also were unwavering in their belief in the authenticity of the skull.

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