Making a mark. It’s such a basic urge, and when I’m at the beach, I can’t resist. The sand is so yummy to carve in, and there are plenty of sharp shells around to make the perfect markers.

 Mira can’t resist either. At four and a half, she’s discovering the power of inscription. ‘These are bird footprints,’ she tells me,

 and I muse on how our ancestors made their marks on cave walls with pieces of charcoal or red ochre, marks not so very different from these bird footprints,

 made with such total absorption, in magical inner space.

 The sand yields so easily to a little hand. When the Sumerians invented writing, thousands of years ago, they carved marks just like this.

The afternoon slips by as we play under the tangle of pohutukawa branches. . .

We leave a necklace for a mermaid. She will swim out of the sea at dusk and pick it up, and in the morning it will be gone. As will our marks.