On New Year’s Day I took the family out for an evening walk on the ranch. Along the verges, lush after rains, I urged our children, Eve and Rider, to help me collect specimens of different plants, or identify wildlife spoor or scat. I wore shorts and flip-flops. As usual I was talking too much to my wife Claire, when I was stunned into silence by Eve, who cried out loudly, as if the world was ending, and pointed at the ground in front of me.