together, the music from the thousand singing serpents swells to magnificence, flooding the entire area with a sound of mesmerizing beauty. It is also a plaintive sound of longing and anticipation, the universal cry of long-suppressed desire on the verge of being satisfied.
The great longnecked serpents of Canthor conclude their annual mating symphony as the two oceans become one and the inhabitants of each ocean seek out their lifelong mates in the united waters. There are five nights out of each Canthorean year when the tidal forces act together to submerge the isthmus and permit the sexual mixing of the serpents. Five nights of love play and frolicking, of renewal and promise, before the requisite return to the separate oceans and a year of waiting for the great tide to come again.
For the little ones, the new serpents placed into gestation by the last annual gathering and hatched by their mothers in the eastern ocean, the great tide is a time of excitement and sadness. They must now separate from their playmates, leave their infancy behind. Half must depart from their mothers as well and go to swim among the cobalt blue adults that they have never met. This half, having lived their lives among their mothers' friends exclusively, will swim above and across the isthmus on the fifth night alongside their fathers. Once into the western ocean, their pale blue necks will begin to deepen in color as they begin the transition through puberty into adulthood. And next year, their tiny voices will have matured just enough that each of them may detect some arousing and positive response to his call during the mating symphony
Thousands of years pass on the planet Canthor. The forces of change conspire against the beautiful bluenecked serpents. First a major ice age comes to the world, locking up more of the planet's water in perennial polar caps and lowering the seas. The number of days that the great tide submerges the isthmus is reduced to four, then three, and finally only two. The elaborate mating ritual of the serpents, worked out over hundreds of generations, works best for a five-night courtship. For the several hundred years that only two nights are available for mating, the number of serpent offspring produced each year drops precipitously. The total number of Canthorean serpents becomes dangerously small.
At length the radiative output of the dual suns increases slightly again and Canthor emerges from its ice age. The sea level rises and the number of days for mating returns eventually to five. The serpent symphony, which had added a saddened counterpoint during the trying years of reduced mating nights, again becomes charged with joy. For several generations the number of serpents increases. But then the lovely creatures encounter another foe.
Evolving elsewhere on Canthor for almost a million years has been another intelligent species, a fierce, squat creature with an insatiable appetite for control. The ice age stimulated the rapid evolution of these trolls by enforcing a strict survival of the fittest that naturally selected those individuals with the most resources (intelligence and power primarily) and, in a sense, purified the troll gene pool.
The troll species that emerges from the thousands of years of ice domination on Canthor is sharper and more capable of dealing with the rest of its environment. It has become a tool maker and has learned how to use the riches of the planet for its benefit. No other living creatures on Canthor can match the cleverness of the trolls or threaten their existence. So the trolls proliferate around the planet, dominating it completely with their rapaciousness.
The bluenecked serpents have had no natural enemies on Canthor for hundreds of millennia. Therefore they have not retained the aggression and territoriality necessary to survive when threatened. Their diet has always consisted primarily of plants and animals that fill the Canthorean oceans. The seas provide a virtual cornucopia of food, so it does not make much of an impression upon the serpents when the trolls begin to farm the oceans for their own food. To the trolls, however, whose greed for territory knows no bounds, the serpents represent at least a rival for the plenty of the oceans and possibly, because of their size and intelligence, even a survival threat.
It is again the time of the great tide and the male longnecked serpents have completed their ocean migration on time, swarming as usual just opposite the great volcanic cliffs. There are only a few hundred male serpents now, down markedly