Nature most often gives signals of Momentous Change before it happens. Some events happen at an amazing pace; the warning timeframe can be brief indeed.
Part of our species’ success rests on our ability to Pay Attention. When it’s time to pack up and move out, one must. You get one warning; it’s foolhardy to wait for the second notice. Admittedly, it used to be easier to go somewhere else; Back Then there was somewhere else to go.
Because nothing is entirely predictable, We recommend staying in shape, in case an exit is ultra-hasty. If We can’t be clever, We can be Quick.