They are the mechanism by which the “mother of all waters” description becomes literally true — the water that falls on the summit eventually reaches the river systems that water the surrounding region.

Endemism: A Number That Tells A Story

The percentage of plant species found only on tepui summits — species endemic to the Pantepui region — is, by various estimates, approximately 35 to 50 percent of the total tepui flora.

Some summits have even higher endemism rates for specific plant groups.

This number is extraordinary.

In most plant communities, the proportion of endemic species — species found nowhere else — is much lower.

High endemism rates typically indicate long isolation, specific environmental conditions that have driven unique evolutionary responses, and the absence of the gene flow between populations that would otherwise prevent divergence.