Analyze the "Saber-Tooth Curriculum" text. How did changes in the environment affect the educational system and the community's survival?

Here's the text from the image: 1:1 THE SABER-TOOTH CURRICULUM happy in the possession of adequate meat, skins, and security. It is to be supposed that all would have gone well forever with this good educational system if conditions of life in that community had remained forever the same. But conditions changed, and life which had once been so safe and happy in the cave-realm valley became insecure and disturbing. A new ice age was approaching in that part of the world. A great glacier came down from the neighboring mountain range to the north. Year after year it crept closer and closer to the headwaters of the creek which ran through the tribe's valley, until at length it reached the stream and began to melt into the water. Dirt and gravel which the glacier had collected on its long journey were dropped into the creek. The water grew muddy. What had once been a crystal-clear stream in which one could see easily to the bottom was now a milky stream into which one could not see at all. At once the life of the community was changed in one very important respect. It was no longer possible to catch fish with the bare hands. The fish could not be seen in the muddy water. For some years, moreover, the fish in this creek had been getting more timid, agile, and intelligent. The stupid, clumsy, brave fish, of which originally there had been a great many, had been caught with the bare hands for fish generation after fish generation, until only fish of superior intelligence and agility were left. These smart fish, hiding in the muddy water under the newly deposited glacial boulders, eluded the hands of the most expertly trained fish-grabbers. Those tribesmen who had studied advanced fish-grabbing in the secondary school could do no better than their less well-educated fellows who had taken only an elementary course in the subject, and even the university graduates with majors in ichthyology were baffled by the problem. No matter how good a man's fish-grabbing education had been, he could not grab fish when he could not find fish to grab. The melting waters of the approaching ice sheet also made the country wetter. The ground became marshy far back from the banks of the creek. The stupid woolly horses, standing only five or six hands high and running on four-toed front feet and three-toed hind feet, although admirable objects for clubbing, had one dangerous characteristic. They were ambitious. They all wanted to learn to run on their middle toes. They all had visions of becoming powerful and aggressive animals instead of little and timid ones. 3 done, 2 left today. You're making progress.