Crocodile Jaws: Their One-Way Strength
The muscles it uses to open its jaws are much weaker than those used to snap it shut
You do not want to get the wrong side of a crocodile or alligator, and by the wrong side I mean inside its jaws as opposed to outside!
A dog bite is unpleasant enough — I should know, as I bear the scars from the attentions of a German shepherd dog a few years ago! — but a dog can only snap its jaws shut with a force of 100 pounds per square inch. This is enough to cause a nasty injury to the top of one’s finger, but a croc could easily remove the whole hand, given that its jaw can exert a force of 3,000 pounds per square inch.
Any small creature that is unfortunate enough to be snapped up by a crocodile is highly unlikely to see daylight again, its bones being crushed to pulp in no time at all.
However, despite the immense strength of the muscles that close a crocodile’s jaw (the same applies to alligators and caymans), those that open the jaw are considerably weaker. This means that it is possible to escape being eaten as long as one can prevent the jaws from opening in the first place, and this can indeed be done. It has been suggested that some people would be able to hold a croc’s jaws shut with just one hand — presumably quite a large one!