Wood-Boring Beetles

Today, me and my Dad were hiking.  We found a piece of wood that a whole bunch of squiggly line marks on it.  Me and my Dad were wondering, was it done by a human?  Was it done by a worm?  Or something else?  When we got home, we looked it up.  It was actually wood-boring beetles.  Their larvae eat the wood and make squiggle lines.  Those are one of the creatures I never knew about!