Sharkteeth in the Santa Susana Mountains

Los Angeles has a rich fossil history right in our own backyard, and high atop the Pico Formation (a ~2 million year old stratigraphic unit) you can pluck shark (and other vertebrate!) teeth right out of the mountainside. Fun thought experiment: Why (and how!?) are there sharkteeth in the top of a mountain?

In this photo, Natural History Museum paleontologist Lindsay Walker takes a data sample on a recent field dig working alongside the Southern California Paleontological Society to establish the biodiveristy of L.A's fossil record during the Pliocene.