Their neural patterns... they're entirely too complex for a non-sentient species. That one back there was the first live one I could get close enough to for a thorough scan and well... while insectoids are less common than humanoids or even reptilians, they do exist. Admittedly I am less familiar with them than I am with the others, but I'm still certain from my readings that despite their behavior, they are intelligent people. Something is wrong with them and I intend to find out what.