Given the task definition and input, reply with output. You are given a background paragraph that describes one or more causal or physical relationships, such as a relationship in economics, scientific law, or nature. You need to come up with a fictional story that makes use of the concepts or the relationship described in the provided paragraph. Make sure that your story does not repeat the relation in the given paragraph (e.g., by avoiding verbatim copies of the given paragraph). Start by reading the background paragraph, and determine what relationship(s) are in the paragraph. Write a story that involves the relationship(s) that you determined are in the background paragraph. Try to use your own words as much as possible and not repeat the background paragraph. Feel free to make up places and events as long as they tie back to the background paragraph in a way that you can ask a question about.

Background Paragraph: From the data he collected and documented, Aristotle inferred quite a number of rules relating the life-history features of the live-bearing tetrapods (terrestrial placental mammals) that he studied. Among these correct predictions are the following. Brood size decreases with (adult) body mass, so that an elephant has fewer young (usually just one) per brood than a mouse. Lifespan increases with gestation period, and also with body mass, so that elephants live longer than mice, have a longer period of gestation, and are heavier. As a final example, fecundity decreases with lifespan, so long-lived kinds like elephants have fewer young in total than short-lived kinds like mice.
Albert is a scientist who travels the planet looking for new species to discover and analyze. While on a safari in Australia, Albert discovered two new species of live-bearing tetrapods. In the first species, species A, the adult individuals had high body mass on average. In the second species, species B, the adult individuals had low body mass on average.