What method was used for timekeeping in the Upper Palaeolithic?

The method of using notches on stone for timekeeping in the Upper Palaeolithic is significant because it reflects the early human practice of creating physical representations of time to track events and cycles. This method would have allowed prehistoric peoples to note important occurrences, possibly related to hunting seasons, lunar phases, or other rhythmic cycles in their environment. Notching provides a tangible and direct way for individuals to record information that could easily be referenced, enabling a form of calendrical tracking before the development of more sophisticated timekeeping methods.

In contrast, the other options do not accurately represent the timekeeping practices of that era. For instance, calendars carved in wood would have required materials that may not have been widely used or preserved during the Upper Palaeolithic. Rope knotting, while an inventive way of measuring time or quantities, does not have direct evidence supporting its use specifically for timekeeping in this period. Written records on clay tablets pertain to much later historical periods, reflecting developments in civilization that occurred well after the Upper Palaeolithic. Thus, notches on stone stand out as the most plausible and historically supported form of timekeeping during that era.