Mammoths in our midst: The proboscideans of Anza-Borrego Desert State Park ®, Southern California, USA

Abstract

Anza-Borrego Desert State Park ® (ABDSP) has an exceptional proboscidean fossil record. The remains of Gomphotheriidae and Elephantidae span over 10 Ma and encompass over eighty productive sites. The most numerous of the proboscideans are the mammoths. Significant specimens include one of the youngest Gomphotherium and the most complete skeleton of Mammuthus meridionalis in North America. Over 6 km of fossiliferous sediments spans the Miocene–Pliocene and Pliocene–Pleistocene boundaries and provides a continuous record of changing environments. Over 550 taxa of aquatic and terrestrial plants, marine and lacustrine invertebrates, and marine, fresh water and terrestrial vertebrates are represented. Present are both Asian and South American immigrant mammals. M. meridionalis and M. columbi (= M. imperator) regionally co-existed here. A specimen from the Diablo Formation extends the temporal range of Gomphotherium in North America nearly one million years into the middle Blancan.