Triangles are commonly found in nature due to their structural strength. The document discusses examples of triangles in the Bermuda Triangle where ships and planes have disappeared, in trees where branches and leaves form triangular shapes, in plants where many have triform leaf patterns, and in mountains which take on triangular shapes due to tectonic plate movement. Triangles are the strongest geometric shape and are widely used in architecture for building stability, and they are also prevalent in natural formations throughout the world.