EPOW - Ecology Picture of the Week

Termite Condos 
of the Congo

Termite Nest on Cleistopholis patens tree
Democratic Republic of the Congo

Explanation:  What are these strange brackets that ring this tree, here along the flooded forested shores of the Ubange River in the middle of the Congo River basin?  Why, this is condo living for invertebrates!  

More specifically, these are termite nests that have nearly completely covered the trunk of this Cleistopholis patens tree.  

Why would termites build such structures?  A common explanation has to do with the fact that they live in a rainforest.  Guess what ... here, it rains a great deal.  The scalloped and imbricate (overlapping) architecture works a lot like the "drip tips" on leaves of tropical plants.  It helps to shed and funnel rainwater off the surface.  And in so doing, It may even help to reduce the incidence of infestation by fungus, as has been demonstrated experimentally with tropical leaves.  (To my knowledge, this potential advantage of the "condo" shape of these termite mounds has not been advanced or tested.)

So this is quite an amazing structure, and an amazing convergence of function between insects and plants.  
  

Even the runways of termite highways on the surface of the tree are covered by their cement-like excrement, forming water-tight tunnels in which they traverse with impunity in the torrential rainforest downpours.

High up on other trees occur different structures of termite nests -- likely made by other termite species.  

But these, too, are encased in the termite's plaster and are hard as dried cement ...  which helps protect from harsh stormy weather but also protects the insects from all but the most persistent and strong predator invaders, such as the scaly anteater or pangolin that digs into the nests with their long, sharp claws.