Other mistake: For someone who has been living on a desert island for at least 10 years, Emmeline seems to have discovered a beauty salon hidden in the paradise. In the close up shots of her hands, she has remarkably nice manicured nails.
Other mistake: This mistake happened right after Richard evicted Emmeline from their hut. We see Emmeline under some rocks and it is raining. See has a makeshift wall made of palm leaves. The rain is coming down to the left, but the wall comes down the opposite way to the right, against the wind and the rain. The director mentioned on the commentary they used ropes to do this. (00:57:35)
Answer: The ending is meant to be ambiguous, and is identical to the ending of the original novel on which the film is based. It is never answered whether they are alive or not.
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