Threatening behavior causes a fight-or-flight response in animals, and fear also causes adrenaline to surge, which is part of the fight or flight response. Given these facts, an animal attacking another animal may cause among the following options:
- dopamine to increase
 - hypothyroidism
 - cause their death
 - decrease stamina
 - adrenaline to surge
 - population movement
 - insulin decrease
 - growth hormone production


 

     adrenaline to surge    