‘Bones,’ said Andres evenly. Rusel thought she seemed oddly excited, stirred by the degraded spectacle before her. ‘But there’s too much debris here to be accounted for by their occasional raids into transient country.’

Rusel shuddered. ‘So they eat each other too.’

‘No. Not quite. The old eat the young; mothers eat their children. It is their way.’

‘Oh, Lethe . . .’ Andres was right; Rusel couldn’t throw up. But he was aware of his body, cradled by the concerned Ship, thrashing feebly in distress.

Andres said dispassionately, ‘I don’t understand your reaction.’

‘I didn’t know—’

‘You should have thought it through - thought through the consequences of your decision to let these creatures live.’

‘You are a monster, Andres.’

She laughed without humour.

Of course he knew what these animals were. They were the Autarchs - or the distant descendants of the long-lived, inbred clan who had once ruled over the transients. Over nearly twenty thousand years selection pressure had worked relentlessly, and the gene complex that had given them their advantage over the transients in the first place - genes for longevity, a propensity injected into the human genome by the Qax - had found full expression. And meanwhile, in the sterile nurture of this place, they had had even less reason to waste precious energy on large brains.

As time had passed they had lived longer and longer, but thought less and less. Now these Autarchs were all but immortal, and all but mindless.

‘They’re actually rather fascinating,’ Andres said cheerfully. ‘I’ve been trying to understand their ecology, if you will.’

‘Ecology? Then maybe you can explain how it can benefit a creature to treat its children so. Those young seem to be farmed. Life is about the preservation of genes: even in this artificial little world of ours, that remains true. So how does eating your kids help achieve that? . . . Ah.’ He gazed at the hairy creatures before him. ‘But these Autarchs are not mortal.’

‘Exactly. They lost their minds, but they stayed immortal. And when mind had gone, natural selection worked with what it found.’

Even for these strange creatures, the interests of the genes were paramount. But now a new strategy had to be worked out. It had been foreshadowed in the lives of the first Autarchs. There was no room to spread the genes by expanding the population - but if individuals could become effectively immortal, the genes could survive through them.

Andres said, ‘But simple longevity wasn’t enough. Even the longest-lived will die through some accident eventually. The genes themselves can be damaged, through radiation exposure for instance. Copying is safer! For their own preservation the genes need to see some children produced, and for some, the smartest and strongest, to survive.