At the end of the last ice age, early humans crisscrossed the Americas following seasons, rivers and game, often with a trusty spear in hand. Nearly 13,000 years later, archaeologists are using those spearheads to study how America's first inhabitants understood risk.
Source: [Phys.org](https://phys.org/news/2026-09-ancient-spearheads-reveal-ice-age.html)