Idiots.
Just a few things that have bugged me about this show.
Modern weapons do not hurt or even scare prehistoric men.
When going on a rescue mission presume everything will be ok and don't take anything that might help you if it doesn't.
Stuck in a cave system that's got natural sunlight clearly coming though the roof make sure remind everyone you need to find your way to the surface, sunlight is no indication of a possible way out.
And with all the vicious wildlife multiple kidnapping and other protetial threats the best thing to do is not build any kind of perimeter defense.
I understand you have to let something's go in tv but I'm fed up of idiots being in charge of groups.