We are excavating in a region of the old phosphate mine called E Quarry, which is one of the richest fossil areas in the park. During mining excavations in the ’50s-’70s, they started finding fossils near the bottom of the main phosphate-rich deposit. Dr. Brett Hendey was allowed to collect fossils from the park and excavate a few areas to record the stratigraphy.
Although the current collection of Langebaanweg fossils numbers over a million specimens, Hendey estimated that about 80 percent of the fossils from the mined layer was destroyed. The two main fossil-bearing layers occur at the base of the thick Muishond Fontein Pelletal Phosphorite Member (MPPM) and in the underlying and thinner Langeberg Quartzose Sand Member (LQSM). The MPPM was heavily mined, but most of the fossils in the member probably represented a reworking of fossils from the white, sandy LQSM.
When the fossil park opened, they wanted to display a fossil-rich layer for the public and began to excavate the area that we are now working in. Because they did not encounter a clear exemplar layer, they moved to another site where they found an awesome bone bed of Sivatheres, short-necked, long-horned giraffes that are now extinct. The original “unloved” site was backfilled, and some of the walls collapsed. The field school plan of attack is to clear out all this backfill and wall-fall (which does contain fossils) till we reach the LQSM, which has a sharp contact with the overlying MPPM. This cleaning will prepare the LQSM to be excavated in the future.
We have two to four students excavating in one by one meter squares. One to two “bucket brigade” students transport the excavated sediments outside to our two sievers, who sieve the sediment through a three mm screen. They then take the material from the sieve to our sorters who use trays and sort through the material and separate the fossils for bagging.
Depending on the density of the sediment, we might have a backup in sorting and sieving (if the material is soft) or have students sitting around waiting for sediment if the sediment is hard and takes longer to excavate. That’s when we teaching assistants pounce, quizzing the students on osteology or teaching them species names of mammals that they will see on our safari at Kruger Park in two weeks. Although it might sound incredibly exciting to be working here, there are periods of boredom, when activity is at a low.
So far, we have found tons of fossils, as expected: bovid and Sivathere teeth and postcrania, including a large chunk of Sivathere mandible with teeth; carnivore teeth and postcrania, especially seals (attesting to the marine-terrestrial interface in the past); lots of microfauna, including rodent and rabbit incisors and frog skeletal remains; and three shark teeth. Still no primates, but I can feel them under there!
In the afternoons this week, students are working on research projects that will be presented next week to us and to the public. Next week we will also be surveying at the nearby site of Elandsfontein where Homo heidelbergensis remains have been found—stay tuned for the exciting continuation!
More info/bio: Amy Shapiro is starting her second year in the PhD program of the ASU School of Human Evolution and Social Change studying paleoecology and paleoanthropology with professor Kaye Reed as her advisor. Amy’s interests include the evolution, adaptation, and biogeography of African mammals and paleoecology of Africa during the evolution of hominins. Last fall, she was a teaching assistant for the IHO Hadar Field School in Ethiopia assisting professors Kaye Reed and Chris Campisano. This is her second year supervising student excavation at Langebaanweg.