Plant "Decisions"

 A questions that has always fascinated me when looking at plants: how do they decide when and where to produce a branch?  Our Rubber Plant has survived man traumas including cat attacks and a fall off a counter that resulted in its coming entirely out of its pot and breaking a few smaller branches.  We carefully returned it to its pot after that last catastrophe and added some nutritious soil and water, and Voila!  it's still alive, although a bit droopy looking. 

But recently our plant produced this fast-growing branch near its base.  If this were a commercial fruit tree or other plant whose growth pattern we were trying to control, we would call it a sucker.  In this case, it might be the way the plant would attempt to survival if nearly everything above it were to die and fall off, like an old tree.  A lot of research has gone into this sort of question in recent years and has included analogous questions pertaining to the animal kingdom.  For instance, how does an animal blastula decide when and where to grow and arm, a leg, a tail, eyes, etc.  In college, I was fascinated by the study of embryology.  We'd study cross-sections of many types of animals, notably chickens and mice, in various stages of development from egg to birth.  We were amazed by the sequence of changes and the evolutionary relationships among the various animal categories, such as the gill slits that humans have at a certain stage, and the tail, and how these parts would turn into different things during development, such as parts of the middle ear, the lower jaw, and so on.  But way back then, the science of figuring out how these changes are triggered had barely begun.  In fact the structure of DNA had only recently been figured out.  As the science gets more complicated, and I get left behind, I can still take pleasure in being able to think of questions much faster than my ability or anyone else's to find answers.