A primeira história pode ser " The Island of One " de Eve Bunting
When an asteroid threatens to destroy their space island, the sole survivors of the destruction of Earth must find a new place to go.
Cite o livro do Google :
"There were nine hundred of us using up supplies faster than we could recreate them. Seth's father said it was a pity we weren't all smaller. We'd need less space, less food, less energy. Maybe all experiments start with crazy ideas." Seth was beginning to understand. "The R Factor. The Reduction Factor. If it worked we wouldn't even know. We'd all become small together. There would be no freaks." "Exactly."
Eu não vejo qual (se houver) poderia ser a segunda história, mas os outros livros da série "Ficção científica criativa" são: "O Dia dos Terráqueos", "Os Seguidores", "A Máscara", "O Espelho Planet", "O Povo Robô", "O Povo Espacial" e "O Povo Submarino" (o mesmo autor).