SciencePrecambrian to presentglobalhigh confidence

Animals—including humans, dinosaurs, and trilobites—appeared only about 85 percent of the way through Earth's history.

Notes on verification

Multiple peer-reviewed and institutional sources (Biological Bulletin, NASA, Paleontological Society, Andrew Knoll's own research) converge on the same order of magnitude, confirming animals emerged only in the last ~15% of Earth's history. [tier=gold indep_score=0.988 clusters=4 claim_tier=notable]

Sources