Hyenas hunt in packs. They are raiders and opportunists. They attack when they see weakness. They watch to see who is young, vulnerable and gullible. When they see that we have left some section of our society behind they cut them off from the rest of us, encircle them and bring them.
The hyenas are the extremists. They make their own kills and they live off whatever carrion they find. Jackals are moderates. They want to stay close to us so our suspicions are not aroused. They creep around trying to be inconspicuous and they live off our scraps.