Plain-Brown Wood Creeper

I saw several plain-brown woodcreepers at Tinamu Reserve, in the jungle forest on the sides of trees. 

Note the nape feathers forming a crest.

It is plain brown, above and below, unlike most other woodcreepers which have streaking. It can raise its crown feathers to make a slight crest. It has a narrow supercilium (a stripe that runs from the beak, above the eye toward the back of the head) and a buff stripe below the eye. 

It primarily eats ants and other insects and looks somewhat like a woodpecker how it stands on the side of a tree. It is found from Honduras to northern Argentina. 

Plain-brown woodcreeper range - from Wikipedia.