He learned that all but those who were cos-ata-lu came up cor-sva-jo, or from the beginning. The egg from which they first developed into tadpole form was deposited, with millions of others, in one of the warm pools and with it a poisonous serum that the carnivora instinctively shunned. Down the warm stream from the pool floated the countless billions of eggs and tadpoles, developing as they drifted slowly toward the sea. Some became tadpoles in the pool, some in the sluggish stream and some not until they reached the great inland sea. In the next stage they became fishes or reptiles, An-Tak was not positive which, and in this form, always developing, they swam far to the south, where, amid the rank and teeming jungles, some of them evolved into amphibians. Always there were those whose development stopped at the first stage, others whose development ceased when they became reptiles, while by far the greater proportion formed the food supply of the ravenous creatures of the deep.
Few indeed were those that eventually developed into baboons and then apes, which was considered by Caspakians the real beginning of evolution. From the egg, then, the individual developed slowly into a higher form, just as the frog's egg develops through various stages from a fish with gills to a frog with lungs. With that thought in mind Bradley discovered that it was not difficult to believe in the possibility of such a scheme—there was nothing new in it.
From the ape the individual, if it survived, slowly developed into the lowest order of man—the Alu—and then by degrees to Bo-lu, Sto-lu, Band-lu, Kro-lu and finally Galu. And in each stage countless millions of other eggs were deposited in the warm pools of the various races and floated down to the great sea to go through a similar process of evolution outside the womb as develops our own young within; but in Caspak the scheme is much more inclusive, for it combines not only individual development but the evolution of species and genera. If an egg survives it goes through all the stages of development that man has passed through during the unthinkable eons since life first moved upon the earth's face.
The final stage—that which the Galus have almost attained and for which all hope—is cos-ata-lu, which literally, means no-egg-man, or one who is born directly as are the young of the outer world of mammals. Some of the Galus produce cos-ata-lu and cos-ata-lo both; the Wieroos only cos-ata-lu—in other words all Wieroos are born male, and so they prey upon the Galus for their women and sometimes capture and torture the Galu men who are cos-ata-lu in an endeavor to learn the secret which they believe will give them unlimited power over all other denizens of Caspak.
No Wieroos come up from the beginning—all are born of the Wieroo fathers and Galu mothers who are cos-ata-lo, and there are very few of the latter owing to the long and precarious stages of development. Seven generations of the same ancestor must come up from the beginning before a cos-ata-lu child may be born; and when one considers the frightful dangers that surround the vital spark from the moment it leaves the warm pool where it has been deposited to float down to the sea amid the voracious creatures that swarm the surface and the deeps and the almost equally unthinkable trials of its effort to survive after it once becomes a land animal and starts northward through the horrors of the Caspakian jungles and forests, it is plainly a wonder that even a single babe has ever been born to a Galu woman.
Seven cycles it requires before the seventh Galu can complete the seventh danger-infested circle since its first Galu ancestor achieved the state of Galu. For ages before, the ancestors of this first Galu may have developed from a Band-lu or Bo-lu egg without ever once completing the whole circle—that is from a Galu egg, back to a fully developed Galu.
Bradley's head was whirling before he even commenced to grasp the complexities of Caspakian evolution; but as the truth slowly filtered into his understanding—as gradually it became possible for him to visualize the scheme, it appeared simpler. In fact, it seemed even less difficult of comprehension than that with which he was familiar.
For several minutes after An-Tak ceased speaking, his voice having trailed off weakly into silence, neither spoke again. Then the Galu recommenced his, "Food! Food! There is a way out!" Bradley tossed him another bit of dried meat, waiting patiently until he had eaten it, this time more slowly.
"What do you mean by saying there is a way out?" he asked.
"He who died here just after I came, told me," replied An-Tak. "He said there was a way out, that he had discovered it but was too weak to use his knowledge. He was trying to tell me how to find it when he died. Oh, Luata, if he had lived but a moment more!"