An exploratory subway shaft dug just down the street from the Los Angeles County Museum of Art has uncovered a treasure trove of fossils in a land where sabre-tooth cats and other early animals once roamed.
Palaeontologists have recovered molluscs, asphalt-saturated sand dollars, pieces of driftwood and Monterey cypress cones.
For palaeontologist Kim Scott the most exciting finds have been a rock embedded with what appears to be part of a sea lion's mouth - perhaps two million years old - and a non-fossilised three-metre-long limb from a digger pine tree that would look right at home today in California woodlands.
"Here on the Miracle Mile is where the best record of life from the last great ice age in the world is found," said Scott, field and laboratory director with Cogstone Resource Management, based in Orange county. In the shaft, she added, "you're walking along an ice age shoreline".
The former Rancho La Brea area of Hancock Park and environs indeed features one of the world's premier paleontological troves. Over the millenniums, petroleum from once massive underground oil fields oozed to the surface, forming bogs that trapped and killed animals and then preserved their skeletons.
Evidence abounds at the tar pits and the George C.Page Museum, just east of the exploratory shaft, where in the heart of urban Los Angeles scientists have uncovered remnants of dire wolves, sabre-toothed cats, ground sloths and other species.
The swimming-pool-size shaft, six metres wide by 12 metres long, is yielding evidence from its depths of a cooler, wetter Pleistocene climate of 100,000 to 330,000 years ago, when Pacific Ocean waves lapped over what is now a bustling Los Angeles street called the Miracle Mile.
Materials from the upper part of the shaft range from the modern era to 50,000 years old. Below that was "near shore" material from 100,000 to at least 330,000 years old, Scott said.
The Los Angeles County Metropolitan Transportation Authority is working with Cogstone and Page Museum researchers to identify and preserve the representative sampling.
McClatchy-Tribune, Associated Press