The diagram below shows when two prehistoric primate species existed in Africa.

![A grid showing the evolutionary time periods for two prehistoric primates, Proconsul and Kenyapithecus. The horizontal axis represents time in 'Millions of years ago' and decreases from left to right, with marked ticks at 25, 20, 15, 10, and 5. There are 10 small grid divisions between consecutive ticks of 5 million years, meaning each division represents 0.5 million years.

Two shaded horizontal rectangular bars show when these species existed:

• The top bar, labeled 'Proconsul', starts at 23.0 million years ago (4 grid divisions to the right of 25) and ends at 14.5 million years ago (1 grid division to the right of 15).
• The bottom bar, labeled 'Kenyapithecus', starts at 16.0 million years ago (2 grid divisions to the left of 15) and ends at 12.0 million years ago (4 grid divisions to the left of 10, or 6 grid divisions to the right of 15).](https://assets.mathsgenie.co.uk/aqa-qb/be2247a8-b3c3-4fec-81ac-96aea6c8c93f.png)