The fossilised tooth of a woolly mammoth has been discovered at a building site in San Francisco.
The tooth, which still has intact enamel, was dug up by a crane operator during an excavation for a new transit centre in the city.
The ten inches long, mud-coloured tooth has been called a ‘significant find’ by local paeleontologists who believe it could be 11,000 years old.
The tooth was found at the construction site of the city's new Transbay Transit Centre, a public transport hub being built in downtown San Francisco.
It is broken in two and missing a chunk, but is otherwise in relatively good condition.
‘It's a big deal, so we can study it, get some age dates which help us figure out tectonics [and] seismicity like the San Andreas Fault,’ Jim Allen, a palaeontologist and geologist for the transit centre project, said.