The Symbols +, -, and 0 Are Used to Show

Multiple Choice

The symbols +, -, and 0 are used to show the results of interactions between individuals and groups of individuals. The symbol + denotes a positive interaction, - denotes a negative interaction, and 0 denotes interactions in which individuals are not affected. The first symbol refers to the first organism mentioned. Which fact is correct when describing species interactions?

A) +/0 will always remain such.
B) A +/- interaction could shift to +/0 or +/+ over time, depending on other factors such as competition, population density, or environmental changes.
C) Species interactions occur in isolation and cannot affect the structure of ecological communities.
D) A -/- interaction benefits both of the species in the relationship.