New Scientist

Image: Citron

Nice fangs, shame about the bite. The oversize fangs of some dragonfish may help them to snap their weak jaws shut around prey, improving their odds of bagging a meal.

The dragonfish family (Stomiidae) go after large prey, and so have jaws that open wide. Closing them quickly is not easy, says Christopher Kenaley of Harvard University, since drag increases exponentially with jaw length, and rises even more if bulky prey are sticking out the front. What’s more, dragonfish jaw muscles are very weak.

Kenaley built a computer model of the jaws and found that shutting them around prey lying on its side took up to 1 second – more than enough time to allow it to get away. However, that dropped to just 125 milliseconds when the prey was lodged upright between the teeth.

Kenaley says the results suggest the fangs may not just impale prey as previously thought but help keep it in the best orientation to reduce drag on the jaw when it shuts. Read more on newscientist.com…