Abstract:
Plants stand still. This is as true in Amazonian rainforest as it is in boreal coniferous forest. As the
architects of every medieval castle understood, if you are fixed in place, your past experiences (natural
selection) lead you to develop (evolve) both intense standing defences and facultative ones. Furthermore,
which defences are present at any given time reflect at least four quite different processes: how much
resources you have to build and maintain, the traits of past and present attackers, and the structure of
the entire edifice. when a new defence is being considered. Finally, by the possession of ever more
defences, the castle is rendered ever more immobile (physically, culturally), ever more a long-term
investment, and ever more vulnerable if the defences are breached. Natural selection has generated the
above pattern in plants just as it has done in humans, and in the lowland tropical rainforests of the world
we find the epitome of the lesson. It is here that a plant stands against its herbivores with little or no
help from cold winters, harsh droughts, irregular growing seasons, low species richness of herbivores or
competitors, high quality population cueing systems, and all the other little ways (besides their intrinsic
personal defences) that plants may use to defend themselves against animal herbivores or that may result
in lower populations of herbivores.
