What were among the first markers of time used by ancient civilizations?

Among the first markers of time used by ancient civilizations were the seasons, sun, and moon. Early societies observed natural phenomena to measure time, relying on the cyclical patterns observed in nature. The changing seasons provided clear indicators of the passage of time, influencing agricultural practices and cultural activities.

Additionally, the sun's position in the sky allowed for daily timekeeping, with sundials being one of the earliest instruments created to measure time based on the sun's movement. The moon’s phases further contributed to timekeeping by helping to track months and cycles, which were essential for calendars and religious observances.

While other options, such as clocks, mechanical gears, and glass hourglasses, represent more advanced timekeeping technologies that developed later in history, they were not among the initial methods used by ancient civilizations to mark time. The reliance on astronomical bodies and seasonal changes highlights the foundational relationship between humanity and the natural environment in the development of timekeeping practices.