# If the history of the earth represented one year how many days would human evolution occupy?

Sep 2, 2016

Hominids diverged from apes in the last $14.5$ hours of the year representing the age of the Earth.

Anatomically modern humans in the last $23$ minutes of the year.

#### Explanation:

• The age of the Earth is about $4.54$ billion years.

So if we represent the history of the Earth by one year, then $1$ day represents:

$\frac{4.54 \times {10}^{9}}{365.25} \approx 12.5$ million years.

• Hominids separated from apes about $7.5$ million years ago.

So the time of the evolutionary divergence of hominids would be represented by:

$\frac{7.5}{12.5} = 0.6$ days $\approx 14.5$ hours

• Anatomically modern humans date from about $200000$ years ago.

That would be represented by:

$\frac{2 \times {10}^{5}}{12.5 \times {10}^{6}} = 0.016$ days $\approx 23$ minutes.

So anatomically modern humans have been around for the last $23$ minutes of the year representing the age of the Earth.