Coprolites: Taphonomic and paleoecological implications

Recent paleontological collections at Laetoli and Kakesio have yielded a number of coprolites of medium- to large-sized carnivores, and a rare collection of ruminant coprolites. The carnivore coprolites appear to belong to a diversity of taxa, including canids, felids and hyaenids. Their occurrence confirms other lines of evidence that carnivores played an important role in the accumulation and composition of the fossil remains at Laetoli. Ruminant coprolites are extremely rare in the African fossil record, and are the result of unusual preservational conditions. The dung can be attributed to medium- to large-sized ruminants, including Giraffa stillei and at least two species of bovids. The consistency of most of the ruminant dung and the occasional presence of seeds indicates that deposition occurred primarily during or soon after the rainy season, a finding consistent with the sedimentological evidence. The presence of seeds and of coarse particles of herbaceous and woody plant material in several coprolites supports stable isotope and mesowear studies indicating that the ruminants at Laetoli were predominantly mixed feeders.