I'm not an archaeologist, but I play one on the DS.
I guess I never really thought about it, but now I actually think the tree thing is one of the most genuine moments in the movie.
Think about the last time you had a really, really horrible day. Everything goes wrong. You get home. Everything seems fine. And it's some little thing that sets you off. You spill juice on the floor. You stub your toe. You spill something on your favorite shirt.
It's that sense of "Oh, well... at least nothing else can go wrong." And then it does.