Artifact depicts 34,000-year-old lunar phases via notched lines. Marshack identified it as oldest lunar calendar. Humans planned nighttime hunts using full moon predictions. Tracked lunar cycles to predict herd returns in valleys. Wiggly line charts moon's apparent retrograde motion. Gave huge advantage over reactive hominid species. NASA links confirm oldest lunar calendars. Skeptics note majority reject lunar interpretation due to insufficient evidence. Early humans matched modern learning capacity. Markings span long periods matching lunar months. Not mere art but functional sky position mapping. Allowed future event prediction beyond reactivity. Oxford comma fan allegedly carved it.