For me it was very disappointing, so much formula. There were gaping holes in the "story". The biggest being the girl.
WARNING!!! Spoiler Alert !!!
When the man she was living with was shot dead, there was no display of any emotion. Was he her father, rescuer, carer or captor, or worse?
The film did not work for me... even in 3D.
I believe it was the Colonel who mentioned that some soldiers with children ran away. I think she was his daughter but she had started to become so primitive that perhaps she did not have enough human emotion left to grieve. Either way, the movie was not as good as it should have been.
Primitive? It is now scientifically documented that many animals grieve. So even if the humans revert to a more animalistic state, they will still grieve. The child was therefore had a mental disability. But the most likely explanation, is terrible script writing and editing.