Re: is it possible an island of dinosaurs that we have not discovered yet exist

A simple answer would be no.  It is highly improbable that dinosaurs, or 
really, any extinct life-forms could exist on an "undiscovered" island.  
However, it is not utterly impossible.  This is not to say that you should 
run and pack your bags, grab your binoculars and head for Isla Sorna.  
Though there are some phenomenal discoveries of living plants and animals 
that were once thought to be extinct.  Some such examples include the 
recent discoveries of metasequoia (dawn redwood), and the bony fish known 
as the coelacanth (found off of the coast of Madagascar).  

   Science is not good at "proving" something does NOT exist.  Science is 
excellent at describing things that DO exist.  Is there an undiscovered 
island?  Well, we don't know (its undiscovered).  Is it probable? Probably 
not.  With the advent of remote sensing (infrared, satellite photography, 
etc.) geographers, and geologists have looked extensively at the earths 
surface, there is little area that has not been studied to one degree or 
another.  It is not likely that there are undiscovered islands that are 
the big enough to support dinosaur life in the form of the extinct 
critters as we commonly think of them (though one can argue that there 
descendants are plentiful: they are all birds).