The spines on the ants help to protect the insects, but the scientists think the sharp appendages serve another surprising function, given the ants' enormous heads.
"Once you open up the rotational 3-D PDF and see these ants' extraordinary spines, or 'inordinate spinescence' as we phrase it in the study, you can't help but ask why on earth these structures evolved," Sarnat said. "The most obvious answer is defense, but the internal morphology revealed by this new micro-CT scanning technology suggests that the answer might also have something to do with muscle mechanics and powering the huge heads of the soldier ants."
In a related study published in the same journal, the research team described two additional new species of ants found in the Fijian islands. These insects have a much less dramatic appearance, but one -- Pheidole ululevu -- has a big head like the "Game of Thrones" ants. The other, Pheidole kava, was named after a mildly narcotic drink from the Pacific Islands.
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