In my home, I have a window which consists of two panes of overlapping glass separated by a narrow gap to permit air flow between the panes. Behind the glass is a fly screen. This morning I noticed a fly has manoeuvred itself into the space between the glass and the screen. Watching it trying to escape, it becomes apparent its instinct is to move in an upward direction in order to find the way out. Of course, in this case the correct strategy is to crawl or fly down until encountering the gap between the sheets of glass. The fly will never escape if it sticks to its instinctive strategy. It will die of starvation. Perhaps the instinctive strategy to avoid disaster is not always the best one.