Possibly Human-Modified Mammoth Tusk and Bone from the Pleistocene of South Texas

Abstract

Twenty-one species of extinct, large, late Pleistocene mammals have been identified from sand and gravel pits in terrace and valley-fill deposits of the Lower Nueces River of South Texas. A log from the alluvial valley-fill unit that produced most of the fossils has been 14 C dated at 13,230 ± 110 YBP. The distal end of a mammoth tusk from this unit exhibits modifications that may not be the result of natural processes and may have been altered by contemporaneous humans. The 185 mm long tusk tip is rounded on the distal end, suggesting possible use as burnisher-billet. The tusk segment also has a curved, rounded, and polished groove 3 cm wide and 1 cm deep transverse to the long axis. The groove may have resulted from being used as a thong stretcher, hide softener, or shaft straightener. Alternatively, the groove may be a natural feature, formed by the stripping of leaves from twigs, an activity noted in living elephants. Sections of a limb bone have marks that may have been caused by butchering activities.