LOS ANGELES – As part of the crew that digs a subway extension under the streets of Los Angeles, Ashley Leger always keeps her security equipment nearby.
When your phone vibrates, you quickly don a neon vest, helmet and goggles before entering a massive construction site under a boulevard east of the city center.
Those who move the Earth deviate, and Leger gets down on his knees and gently brushes the dirt from a point indicated by a member of his team. Her heart beats faster because there is a possibility that she discovers what she calls "the great find"
. Leger is a paleontologist looking for fossils in the middle of a city instead of an open plain or desert. She works for a company hired by transportation officials in Los Angeles to keep paleontologists on hand while workers extend a subway line to the west side of the city.
"They are making sure they are recovering every fossil that might appear," Leger says of his monitor team. "They call me when things are big and we have to lead an excavation."
Since work began on the extension in 2014, fossilized remains have routinely emerged from creatures that roamed the grasslands and forests that covered the region during the last ice age, about 10,000 years ago.
Include a partial rabbit jaw, mastodon tooth, camel front leg, bison vertebrae and a bone of ankles and teeth of a horse.
But the discovery that makes Leger shake his head in disbelief came a year ago, shortly after the construction of the second phase of the project began. He was at home preparing to go to bed when he received a call from one of his monitors.
"It looks great," he said.
The next morning, Leger knelt on the site and recognized what appeared to be a partial elephant skull.
It turned out to be much more. After 15 hours of painstaking digging, the team discovered an intact skull of a juvenile mammoth.
"It's an absolute dream come true for me," said Leger, who spent the previous decade on a giant site in South Dakota with no discoveries close to the size of one in Los Angeles. "It's the only fossil you always want to find in your career."
California's stringent environmental laws require that scientists be available at certain construction sites.
Paleontologists have attended all excavations of the New York subway since the 1990s, when work began on the city's inaugural line, said Dave Sotero, spokesman for the Los Angeles Metropolitan Transportation Authority. Angels
Pay for the paleontology personnel of Cogstone Resource Management is taken into account in the cost of the project, he said. When scientists are brought in to see what equipment they may have unearthed, work on the project continues, albeit at a different location.
"Our teams try to be as aware as possible to help them do their jobs," Sotero said, adding that when the mammoth skull was discovered, the construction workers helped take it to the mouth of the site.
From there, the skull was dragged a kilometer and a half to La Brea Tar Wells and Los Angeles Museum, home to one of the richest fossil sites in the United States.
Assistant curator Dr. Emily Lindsey called it a "pretty remarkable find," noting that while thousands of remains of ghouls and saber-toothed wolves have been discovered in L.A., there have only been about 30 mammoths.
A few hundred pounds and the size of an armchair, the skull is especially rare because both fangs were united. It is being studied and is available for public viewing inside the Fossil Lab with glass walls of the museum.
With a nod to Hollywood, the Colombian mammoth from 8 to 12 years old was called Hayden, by the actress Hayden Panettiere, presented in the television series "Nashville" and "Heroes".
The Cogstone monitor at the construction site had been watching it on television before seeing the speck of bone that turned out to be the intact skull.
Similar efforts have revealed underground treasures during excavations in other cities.
Workers at a San Diego construction site found fossils that include parts of a mammoth and a gray whale and several layers of ancient sea shells.
Last year, crews working in a development near the Boston Seaport discovered a 50-foot wooden boat that possibly dated to the late 18th century.
Lindsey praised California's efforts to ensure that science and urban development overlap, while regretting that the missing treasures were lost before the regulations came into effect in the early 1970s.
"Most of the past is under the earth, so you're only going to find it when you dig," he said. "As the city grows, I'm sure we'll find more fascinating fossil material."