A bit of fun ......

The light conditions today were less than poor so I took this image because I love the texture of tree bark.

Here is a question for you, no, I'm not going to ask you what type of tree it is however if you are confident ....... please feel free to leave a comment.

My question is, what animate object is to be found on the bark ? ..... again, your comments much appreciated if you've got the bottle !.  

No prizes for the winner other than the satisfaction of getting it right.