Tree Defenses

give-and-take tree

Do you think this small palm in Belize tries to discourage small animals from eating its fruit? Perhaps it wants birds to eat the fruit to scatter the seeds further - perhaps small animals could break the seeds open and destroy them, whereas birds might eat the fruit and pass the seeds through their systems unharmed...


It is felt that some small trees evolved with spikes to protect themselves from being pushed over by giant sloths after their fruit. The giant sloths are extinct, but genetic memmory lats a long time...

ant acacia

This is an "ant acacia" tree. On the right you will see some small ants on the leaves. These ants never leave the tree - they get everything they need from this tree. Why?

ant acacia

Notice two things: the small yellow spots on the leaves, and the hole in the thorn. The yellow spots are "protein buds" which the tree provides for the ants to eat. The holes provide shelter for the ants. In return the ants are very protective of their tree - killing any caterpillars that try to eat the leaves, and even preventing vines from growing up the tree!

Of course - this picture also points out that many trees in the rainforest have thorns! And some have very irritating sap that you don't want to touch!

© 2001 Stephen Blythe