The Science of Discworld Revised Edition

people?’
    Ponder dared a short pause before answering.
    ‘They’re the library, sir. I suppose. They can remember things. Places to hunt, good waterholes, that sort of thing. And that means they must have some sort of language.’
    ‘It’s a start, I suppose,’ said Ridcully.
    ‘Start, sir? They’ve nearly done it all!’ Ponder put his hand to his ear.
    ‘Oh … and H EX says there’s more, sir. Er … different.’
    ‘How different?’
    ‘In the sea again, sir.’
    ‘Aha,’ said the Senior Wrangler.
    In fact on the sea was more accurate, he had to admit. The colony they found stretched for miles, linking a chain of small rocky islands and sandbanks as beads on a chain of tethered driftwood and rafts of floating seaweed.
    The creatures inhabiting it were another type of lizard. Still extremely dull, the wizards considered, compared to some of the others. They weren’t even an interesting colour and they had hardly any spikes. But they were … busy creatures.
    ‘That seaweed … does it look sort of
regular
to you?’ said the Lecturer in Recent Runes, as they drifted over a crude wall. ‘They’re not
farming
, are they?’
    ‘I think …’ Ponder looked down. The water washed over the wall of rocks. ‘It’s a big cage for fish. The whole lagoon. Er … I think they’ve built the walls like that so the tide lets the fish come in and then they’re stuck when it goes down.’
    Lizards turned their heads as the semi-transparent men floated past , but seemed to treat them as no more than passing shadows.
    ‘They’re harnessing the power of the sea?’ said Ridcully. ‘That’s clever.’
    Lizards were diving at the far side of the lagoon. Some were busy around rock pools on one of the lower islands. Small lizards swam in the shallows. Along one stretch of driftwood walkways, strips of seaweed were drying in the breeze. And over everything was a yip-yipping of conversation. And it
was
conversation, Ponder decided. Animals didn’t wait for other animals to finish. Nor did wizards, of course, but they were a breed apart.
    A little way away, a lizard was carefully painting the skin of another lizard, using a twig and some pigments in half-shells. The one doing the painting was wearing a necklace of different shells, Ponder realized.
    ‘Tools,’ he murmured. ‘Symbols. Abstract thought.
Things
of value … is this a civilization, or are we merely tribal at the moment?’
    ‘Where’s the sun?’ said the Senior Wrangler. ‘It’s always so hazy, and it’s hard to get used to directions here. Wherever you point, it’s at the back of your own head.’
    Rincewind pointed towards the horizon, where there was a red glow behind the clouds.
    ‘I call it Widdershins,’ he said. ‘Just like at home.’
    ‘Ah. The sun sets Widdershins.’
    ‘No. It doesn’t do anything,’ said Rincewind. ‘It stays where it is. The horizon comes up.’
    ‘But it doesn’t fall on us?’
    ‘It tries to, but the other horizon drags us away before it happens.’
    ‘The more time I spend on this globe, the more I feel I should be holding on to something,’ the Dean muttered.
    ‘And the light isn’t reflected around the world?’ said the Senior Wrangler. ‘It is at home. It’s always very beautiful, the glow that comes up through the waterfall.’
    ‘No,’ said Rincewind. ‘It just gets dark, unless the moon is up.’
    ‘And there’s still just the one sun, isn’t there?’ said the Senior Wrangler, a man with something on his mind.
    ‘Yes.’
    ‘We didn’t add another one?’
    ‘No.’
    ‘So … er … what is that light over there?’
    As one wizard, they turned towards the opposite horizon.
    ‘Whoops,’ said the Dean, as the distant thunder died away and lights streamed high across the sky.
    The lizards had heard it too. Ponder looked around. They were lining the walkways, watching the horizon with all the intelligent interest of a thinking creature wondering what the future may hold …
    ‘Let’s get back to the High Energy Magic building before the boiling rain, shall we?’ said Ridcully. ‘This really is too depressing.’

THIRTY-EIGHT
THE DEATH OF DINOSAURS

    LIFE TURNS UP everywhere it can.
    Life turns up everywhere it can’t.
    And just when it seems to have got itself going really comfortably, with a sustainable lifestyle and gradual progress towards higher things, along comes a major catastrophe and sets it back twenty million years. Yet, paradoxically, those same disasters