What share of the 24-hour period does human existence account for in this analogy?

The analogy in the question compares the duration of human existence to a 24-hour period, which represents the entire timeline of life on Earth. In this context, if we consider that human existence has only been present for a very brief moment relative to the age of the Earth, the idea of one quarter of a second illustrates how minimal this time span is.

Humans have been around for approximately 200,000 to 300,000 years, which is a blink in the entirety of Earth’s history, estimated to be about 4.5 billion years. When translated into the analogy of a 24-hour clock, humans would account for only a fraction of that time. Specifically, one quarter of a second effectively communicates how short human existence is when placed alongside the vast timeline of life on the planet. This helps to emphasize the relative recency of human development in the grand scheme of Earth’s lifecycle.