North American beaver beaver may dwell in a bank burrow and bank lodge with an underwater entrance. The beaver dam is constructed using branches from trees the beavers cut down, as well as rocks, grass, and mud. The inner bark, twigs, shoots, and leaves of such trees are also an important part of the beaver's diet. The trees are cut down using their strong incisor teeth. Their front paws are used for digging and carrying and placing materials. The sound of running water dictates when and where a beaver builds its dam. Besides providing a safe home for the beaver, beaver ponds also
What Is This Thing Called Love? (short story) with aliens and sex. According to Asimov the article was mostly based on "Marvel" since its contents had been the raciest. Cele Goldsmith Lalli, editor of "Amazing Stories", requested a satire of the "Playboy" article. Asimov set out to write a story telling how a sex-interested alien and humans might "really" interact. The story appeared in the March 1961 issue of "Amazing" as "Playboy and the Slime God", but when Asimov included it in his 1969 collection "Nightfall and Other Stories" he retitled it "What Is This Thing Called Love?" Goldsmith Lalli rewrote the story's last three paragraphs, a change