The message here is: mess with the primeval forces of Nature, and Nature will get you in the end. It seems that if you wife-swap, have abortions, or run over a kangaroo, you are going to have a lousy weekend. You won't be able to find the beach; ants will mess up your picnic; the chicken will go off pong, the spear-gun will go off ping; and God knows how the lager will stay cold. These and many other 'mysterious' events are so heavily laden with symbolism that any possibility of suspense or credibility is sunk even before Nature can start to get really raw. Walkabout and The Last Wave did it much better.