Free The Ugly Little Boy by Isaac Asimov, Robert Silverberg

pre-agricultural era, possibly going back five or at most ten thousand years.
    But forty thousand?
    She wasn't prepared for that. Would die child they were going to hand her be recognizable at all as human? Had diere even been such a thing as Homo sapiens forty thousand years ago?
    Miss Fellowes found herself wishing she could remember a little of her college anthropology courses of long ago, but right at this moment only the merest shreds of information came to the surface of her mind, and those, Miss Fellowes feared, were hopelessly garbled and distorted. Before true human beings had evolved, there had been the Neanderthal people, yes? Primitive brutish creatures. And the even more primitive Pithecandiropus people had roamed die world before them, and something else with an equally intricate name, and probably some odier kinds of pre-men or sub-men, too, shaggy little naked ape-creatures that could more or less be ccjn-sidered to be our distant ancestors. But how far back in time had all these ancestral people lived? Twenty thousand years ago? Fifty? A hundred thousand? She really knew nothing useful about the time-frame of all this.
    Great God in heaven, am I going to be taking care of an ape-child?
    She began to tremble. Here she was, fussing over incubators and sterile chambers, and they were preparing to toss something very much like a chimpanzee into her lap, weren't they? Weren't they? Some fierce hairy little wild thing with claws and teeth, something that really belonged in a zoo, if anywhere, not in the care of a specialist
    Well, maybe not. Maybe the Neanderthals and the Pithecanthropuses and all those other early forms of human-like life had lived a million years ago and more, and what she'd be getting would be nothing more than a wild little boy. She had coped with wild little boys before.
    Still, it sounded like such an enormous span of time, forty thousand years. The vastness of it dizzied her.
    Forty thousand years?
    Forty thousand years?
     
    9
     
    There was tension in the air. Now the chaotic ballet in die pit below had ceased, and the technicians at die controls were scarcely moving at all. They communicated with one another by means of signals so subtle that it was almost impossible to detect diem-a flick of an eyebrow, the tapping of a ringer on die back of a wrist.
    One man at a microphone spoke into it in a soft monotone, saying things in short phrases that made no sense to Miss Fellowes-numbers, mostly, punctuated by what sounded like phrases in code, cryptic and impenetrable.
    Deveney had taken a seat just next to her. Hoskins was on the other side. Leaning over the balcony railing with an intent stare, the scientific reporter said, "Is there going to be anything for us to see, Dr. Hoskins? Visual effects, I mean."
    "What? No. Nothing till the job is done. We detect indirectly, something on the principle of radar, except that we use mesons rather than radiation. We've been running the meson scans for weeks, tuning and retuning. Mesons reach backward-under the proper conditions. Some are reflected and we have to analyze the reflections, and we feed them back in and use them as guides for the next probe, fining it down until we start approximating the desired level of accuracy."
    "That sounds like a tough job. How can you be sure you've reached the right level?"
    Hoskins smiled, his usual quick one, a cool on-off flash. "We've been at work on this for fifteen years, now. Closer to twenty-five, if you count the work of our 'predecessor company, which developed a lot of the basic principles but wasn't able to break through to real reliability. -Yes, it's tough, Deveney. Very tough. And scary."
    The man at the microphone raised his hand.
    "Scary?" Deveney said.
    "We don't like to fail. I definitely don't. And failure's an ever-present default mode in our operation. We're working in probabilistic areas here. Quantum effects, you understand. The best we can hope for is likeliness, never certainty. That's