Problem:
Question: Is there any skeletal muscle that does not have an antagonist? Excluding circular muscles such as around eye and mouth.
The reason why I am wondering is because in biology normally nothing is ever just like that, there is always an exception. This would be the first biological rule without exception that I came across.
I am thinking of humans only for a start but feel free to include any other animal if any have skeletal muscles without antagonists.
If anyone knows something about it then please provide your opinion.