Given a scientific passage and an answer, generate a question for the given answer.

Example Input: Passage: Population density is the average number of individuals in a population per unit of area or volume. For example, a population of 100 insects that live in an area of 100 square meters has a density of 1 insect per square meter. If the same population lives in an area of only 1 square meter, what is its density? Which population is more crowded? How might crowding affect the health of a population?. Answer: population density
Example Output: What is the term for the average number of individuals in a population per unit of area or volume?

Example Input: Passage: The amount of material left over after a certain number of half-lives can be easily calculated. Answer: pheromone
Example Output: What term is used to describe a chemical released by an animal that affects the behavior or physiology of animals of the same species?

Example Input: Passage: Omnivores eat both producers and consumers. Most people are omnivores, since they eat fruits, vegetables, and grains from plants, and also meat and dairy products from animals. Dogs, bears, and raccoons are also omnivores. Answer: omnivores
Example Output:
What is the name for creatures such as bears and humans that eat both consumers and producers?