But they didn't need the damn things exploding all over the place. And the Universe was full of these vast, gaudy stars, burning off energy and forever quivering on the brink of catastrophic explosions. Such extrovert monsters were simply unnecessary; all the dark races required from a star was a reasonably stable gravity well. The remnants of large stars -- white dwarfs and neutron stars -- were quite satisfactory, and so were immature stars: the brown dwarfs and Jovian gas planets which were warm but not quite large enough for fusion to be initiated.

Cold, dull, and immensely stable. That was how a star should be.

So the photino birds set out to transform the Universe.

The photino birds set up two great programs. The first had been to shape the evolution of new stars. Paul imagined invisible flocks cruising through the vast gas clouds which served as the breeding grounds for new stars; the photino birds had used huge masses to skim layers off protostars and so condemn them to become brown dwarfs, little grander than Jupiter.

The second program had been to rationalize existing stars.

If the things were going to explode or swell up like balloons, the photino birds had reasoned, then they would prefer to accelerate the process and get it out of the way. Then the photino civilization could grow without limit or threat, basking in the long, stately twilight of the Universe.

So the photino birds had settled into the hearts of stars. They infested the core of humanity's original Sun.

For millions of years, unknown to humanity, the photino birds had fed off the Sun's hydrogen-fusing core. Each sip of energy, by each of the photino birds, had lowered the temperature of the core, minutely.

In time, after billions of interactions, the core temperature dropped so far that hydrogen fusion was no longer possible. The core had become a ball of helium, dead, contracting. Meanwhile, a shell of fusing hydrogen burned its way out of the Sun, dropping a rain of helium ash onto the core...

Five billion years early, the Sun left the Main Sequence, and ballooned into a red giant.

With such cool calculation, such oceanic persistence, the photino birds made the stars old.

Soon the first supernovae began. They spread like a plague from the photino birds' center of operation.

And the Xeelee became troubled.

By this time, Paul speculated, the Xeelee were already lords of the baryonic Universe. They had initiated many of their vast cosmic engineering projects, and a host of lesser races had begun to dog their gigantic footsteps.

The Xeelee focused attention on the photino birds' activities, and rapidly came to understand the nature of the threat they faced. In peril was not just the future of the Xeelee themselves, but of all baryonic life.