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This short story concerns an alien creature of some kind that is slowly feeding on the surface of its home planet. It must stay "in its lane" so to speak because others of its species feeds on either side of it. It encounters something in its path which turns out to be a probe from somewhere. The creature can't go around (due to the feeding rules) it so it attempts to go OVER it and ends up inside and is amazed to find itself immersed in "liquid food" (a formula culture provided to sustain any alien samples collected). It suddenly reproduces, even though the alien concedes it was not the right time to do so. AND the food bolsters its intelligence. It argues with its spawn, explaining that "they" must get to the planet's surface. One does but the other does not! Any ideas?