Fossil-Fuel Pollution and Climate Change - A New NEJM Group Series.

Fossil-Fuel Pollution and Climate ChangeThe editors announce a new NEJM Group series on climate change and the increasingly urgent health and care delivery challenges we face. Articles will appear in the , in , and in .

Pre-Clovis projectile points at the Debra L. Friedkin site, Texas-Implications for the Late Pleistocene peopling of the Americas.

Lanceolate projectile points of the Clovis complex and stemmed projectile points of the Western Stemmed Tradition first appeared in North America by ~13 thousand years (ka) ago. The origin, age, and chronological superposition of these stemmed and lanceolate traditions are unclear. At the Debra L.

Evidence of an early projectile point technology in North America at the Gault Site, Texas, USA.

American archeology has long been polarized over the issue of a human presence in the Western Hemisphere earlier than Clovis. As evidence of early sites across North and South America continues to emerge, stone tool assemblages appear more geographically and temporally diverse than traditionally assumed. Within this new framework, the prevailing models of Clovis origins and the peopling of the Americas are being reevaluated.