The trove of fossils, which date back to the Pleistocene Epoch, have also challenged beliefs previously held by paleontologists who study the beasts that called the LA basin home millions of years before the region was covered by a vast ocean.
Under the watchful eyes of paleontologists, tunneling crews with the LA Metropolitan Transportation Authority, or Metro, have been carving out three underground train stations – La Brea Avenue, Fairfax Avenue and La Cienega Boulevard – for a new branch of the Purple Line subway.
While Metro’s giant excavator is carving out the tunnel, paleontologists with Cogstone – a Riverside, California-based company guiding Metro’s paleontological work – diligently examine the mix of clay and sands in the soil looking for any signs of fossils.
“We’re the ones who say, ‘Stop, that doesn’t look like dirt anymore’ and then go investigate if it’s fossil,” Cogstone paleontologist Cassidy Sharp said in an interview.
Sharp discovered the dire wolf fossil as well as others displayed at Monday’s press conference at the La Brea Tar Pits Museum, which is built on the site where hundreds of prehistoric animals are preserved by tar that has seeped up from below the surface for tens of thousands of years.
“You get to be the first human that has ever seen this animal before and I think that’s a really special feeling,” Sharp said, adding that the huge volume of fossils found during recent excavations adds to the “special” nature of the project.
Fossils start showing up about 15 feet below the surface, Sharp said.
“Isn’t is crazy that you’re driving over Wilshire and you have no idea there’s this mammoth below you,” Sharp added.
Sharp said archeologists are also on site in case artifacts from human civilizations are discovered during excavation.
Among the recent discoveries are a largely complete skull of a juvenile Columbian mammoth dubbed “Hayden” – found by crews at the La Brea Station – and fossils of camels and large horses.
Two partial skeletons and a nearly complete skull of a giant ground sloth were also discovered, including one with a nearly complete pelvis which paleontologists nicknamed “Shakira” in honor of the Colombian artist famous for her belly dancing.
Paleontologists also found well-preserved remains of bison – including a 12,900-year-old lower jaw – at the La Cienega station, which yielded more fossils than the two other stations combined.
Bison fossils are common since they dominated the prehistoric Los Angeles basin and were the most common large animal around after plant-eating large horses.
John Harris, who leads Cogstone’s laboratory work identifying fossils, said in an interview that partial sloth skeleton was discovered in sediments that contained fragments of charcoal, indicating the beast was preserved in a mudslide that likely resulted from an ancient wildfire.
“Like today, there’s a wildfire followed by rains which spark a mudflow,” Harris said. “As the mudflows capture people and cars today, they also caught bison and sloths before.”
The fossils of mammoths are uncommon at sites near tar pits – such as Fairfax Station, which is adjacent to the pits at La Brea Tar Pits Museum – since the animals were large enough to pull free from the sticky black traps, Harris said.
Harris also said it was rare for paleontologists to find fossils of saber-toothed cats and dire wolves at La Cienega station, a site which was not a tar pit, since the beasts didn’t usually live in large communities.
Eric Scott, a paleontologist with Cogstone, said in an interview that the fossils discovered during the project will likely end up in the Los Angeles History Museum.