Bones in the Sticky Bubbles: La Brea Tar Pits

The Stickiest Science on Earth

Imagine trying to clean a toy that fell into a giant bowl of thick, black honey—that is what it’s like to be a scientist at the La Brea Tar Pits. For thousands of years, asphalt (which is like natural, gooey tar) bubbled up from the ground in Los Angeles, acting like a giant glue trap for Ice Age animals. When paleontologists find a bone today, it isn't just covered in dirt; it is soaked and stained deep brown by the tar. To get it clean, they have to be very patient. They use special tools like dental picks and cotton swabs with solution to tiny-scrape away the hard gunk, almost like a dentist cleaning the teeth.

The Secret Sauce in the Fossil Lab

Inside the museum’s "Fishbowl" lab, there are paleontologists through big glass windows as they solve these sticky puzzles. Because the tar is so tough, they sometimes have to soak the fossils overnight in a special liquid (some solvent) that dissolves the asphalt without hurting the bone. Once the tar is softened, they use cotton swabs and tiny brushes to gently wash away the leftover grit. They have to be extra careful with fossils like "Zed," a nearly complete Mammoth, because his giant tusks are actually very fragile after being buried for so long.

Mini Treasures in the Mud

The coolest part about fossil prep at La Brea is that the scientists never throw away the "leftover" dirt. The matrix is full of tiny surprises of microfossils. After the big bones like Sabertooth cat skulls are removed, the team uses microscopes to find things as small as a baby mouse’s tooth, a lizard’s toe, or even a ancient beetle’s wing! These tiny pieces are just as important as the big mammoths because they tell us exactly what the weather and plants were like in California 40,000 years ago.

Photo taken at La Brea Tar Pits and Museum, LA