Sorting a sticky situation: Engaging students in sorting and identifying microfossils from La Brea Tar Pit

Although they do not garner the attention of larger, charismatic fossils, small (1 mm – 1 cm) plant and animal remains are invaluable resources for palaeontologists. These “microfossil” taxa are gener- ally confined to their local habitat and therefore provide insight on the nature of past environments and long-term ecosystem change. For decades, the La Brea Tar Pits (LBTP) in Los Angeles, Califor- nia, USA, has incorporated volunteer sorting of microfossils in their daily research agendas to sup- port scientific discovery in their onsite Fossil Lab. A recent grant-funded research project provided an opportunity to study the Rancho La Brea (RLB) microfossils while extending this “community science” activity beyond the walls of the museum and into local classrooms. From 2018 to 2020, nearly 1500 students contributed by sorting matrix into distinct categories: “plant”, “bone”, “shell”, and “other”. We evaluate the success of this project both in terms of producing usable scientific data and in its impact on the students. We found enjoyment was high among students who completed the ac- tivity. Overall, the level of accuracy of student work was less than that of trained volunteers. However, students were consistent in identifying fossils that were most likely to be valuable for research, and predictable errors provided insight into potential improvements. These data can inform planning for future research needs, lab workflows and opportunities for educational outreach at LBTP and other institutions worldwide.