I've never been one to sit still for long--not even in an island paradise. Within a day, I signed up for every trip I could: the rainforest, the radio telescope at Arecibo, Old San Juan and the Bacardi distillery (yes, as in where they make rum.)
As you may be able to see from these pictures, El Yunque is not all that wild. In fact, while most rain forests around the world are losing acreage, El Yunque has been growing, and most of the plants and animals come from other places--mostly from whatever Spaniards provided, but some of the flora and fauna are compliments of the United States Forest Service. (My inner academic is sighing at the lack of citations here, but it's winter break and I'm tired, so you can believe it or not.) The good news is you don't really need to worry about anything attacking you on the pleasant trails that gently slope alongside moss-covered trees and lacy ferns.