People daubing ochre onto subterranean walls. Placing a spread palm on the stone and blowing pigment round to leave their hand’s outline. Carving a reindeer’s antler into a pipe that plays three rising notes. Leaving the cave with smudges on their lips and wrists and foreheads, climbing variously solemn and laughing into the light. This day, this moment, we were here: us. That handful of notes vibrating on, long after it ceases to be audible, the pattern of the outwards air forever altered.

You were born in the grip of a heatwave. All across England, in Ireland too, the sun-scorched land gave up its secrets: the outline of an Iron Age fort, and a Victorian ghost garden; a medieval castle and a World War II airfield. On the radio, they explained these landscape scars: crop 148marks, they are called, and they appear when plants absorb water and nutrients from the ditches where fortifications once stood. I read too that time doesn’t heal wounds – or that it does, but it can also unheal them. A lack of vitamin C means the body’s collagen stores deplete, and old scars resurface and reopen. At sea, sailors in the grip of scurvy would find themselves dying of old, surmounted wounds and childhood injuries considered overcome. I lay on the bed as your brother napped beside me, the rise and fall of his chest, his damp flushed cheeks, the murmur of the radio, thinking of this, of things unknown and known.

As the weeks went on and the waters receded, scientists discovered footsteps on an estuary shore dating back three quarters of a million years. They could, impossible as it seemed, deduce that a woman had walked that way, a healthy woman of about twenty years old and standing one and a half metres tall. Three, or possibly four, children aged between two and eight had walked with her; at one point, she probably carried the youngest. They would have walked northwards across the wet mud, through brackish water, in a climate that was more akin to modern-day Sweden than the east of England today, with cool, mild summers and brutal winters, in search of shellfish and edible plants. The river valley where they walked would have been grazed by woolly mammoths, hippos, a sort of proto-rhinoceros. As they walked, the heels of their feet and then their toes sinking into the mud, a quirk of tides and sand and sedimentation preserved their footprints for all these centuries, millennia, until the 149summer they briefly appeared and, in the act of appearing, vanished.

That is the second thing.

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