Study reveals surprising violence in female Gila monster fights.

A new study has found that female Gila monsters exhibit surprisingly intense and violent aggression towards each other, with biting and lateral rotation resembling the "deathroll" of crocodiles. This behavior is not observed in male-male aggression. The study suggests that female aggression in this species may be related to nest defense and preventing cannibalism. Gila monsters are the largest lizard native to the United States and are largely understudied despite their iconic status as venomous lizards.