A paleoanthropologist discovers a fossilized hominin femur that is 1.8 million years old. If the fossils carbon-14 content has decayed to 0.0075% of its original amount, and the half-life of carbon-14 is 5730 years, approximately how many half-lives have passed, and is carbon-14 dating feasible

Thu, 07 May 2026 18:28:41 +0000

A paleoanthropologist discovers a fossilized hominin femur that is 1.8 million years old. If the fossils’ carbon-14 content has decayed to 0.0075% of its original amount, approximately how many half-lives have passed—and is carbon-14 dating still a reliable method today?
This fossil discovery is sparking renewed interest, not only in scientific circles but also among audiences following cutting-edge research in human origins. With carbon-14 levels reduced to less than one-thousandth of their initial concentration, the decay pattern reveals deep time in a tangible way. But carbon-14 dating faces limits—particularly when working with specimens far older than its effective range. --- **Why This Discovery Is Gaining Attention**
The age of 1.8 million years places this femur in a critical phase of early human evolution, linking regional fossil records to global timelines. For researchers and general audiences, discoveries like this underscore how modern dating tools continue to refine our understanding of deep history. Despite advances, conventional carbon-14 dating—in renowned facilities and independent labs—remains essential for recent prehistoric remains, while emerging techniques support deeper chronologies beyond 50,000 years. ---