The leeches aren't too discriminating ... like the spiky-leaved plant at right, or any trees for that matter. That rash on Mark's left arm? From a toxic tree resin. Oh, and keep an eye out ...

Ibn Battuta, a medieval Muslim traveler, described seeing the “flying leech” while visiting what is today Sri Lanka in the ...

But leeches aren’t just useful at crime scenes. These creatures’ sanguineous appetites have also come in handy for scientists, who are hoping to use them to solve another mystery: the diversity of ...