Final answer:
The relationship between the predator mammal and the plant food source can be determined by substituting the smaller animal population equation into the predator mammal population equation.
Step-by-step explanation:
The relationship between the predator mammal and the plant food source can be determined by the composition of the population equations. Given that P(x) = 4x² + 7 represents the population of the predator mammal depending on the number x of the smaller animal, and s(a) = 4a + 2 represents the population of the smaller animal depending on the amount a of the plant, we can substitute s(a) into P(x) to find the relationship.
Substituting s(a) into P(x):
P(s(a)) = 4(4a + 2)² + 7
Simplifying the expression:
P(s(a)) = 16a² + 16a + 11
Therefore, the relationship between the predator mammal and the plant food source is P(s(a)) = 16a² + 16a + 11.