Sorry, wiki overload there. Did you know that when the rut (or "mating season," if you're not into that whole brevity thing) begins, male yaks engage in threat displays and sparring? Man, I wanna see some yaks fighting! These yaks, they're just kinda rollin' along, man. Which is still awesome, mind you--
AWWWW SHIT, YAK FIGHT.
Apparently whenever Jess attempts to photograph these magnificent beasts, something--be it the click of a shutter or the flash of a...flash--drives them to a frenzy. Her camera is the Rage virus. Her viewfinder is the Fear Gas from Batman.
She seems perturbed by this. Dismayed, even. I'd take it a different way: with one push of a button, I can turn tame yaks into killing machines. Cities will fall.