Ants ... or termites?

Many of the trees had little tunnels running up and down them, right to the top ... and there were ants, which appeared to be using these tunnels ...

 

The Mayan ruins of Xaman-Ha, Playacar, Quintana Roo, Mexico.

 

There are several of these small pyramids in the jungle along the road leading from Playa del Carmen to Playacar.

Done