Nitrogen stable isotopes are useful tools for the study of food web structure because isotope ratios
A) change in predictable ways across trophic levels.
B) often vary among alternative food sources for a consumer.
C) for a predator exactly match the isotope ratio in its prey.
D) both change in predictable ways across trophic levels and often vary among alternative food sources for a consumer.

Question

Quizplus · Accepted Answer

Nitrogen stable isotopes change in predictable ways across trophic levels, meaning that the isotopic signature of a consumer will be enriched compared to its prey. Additionally, nitrogen stable isotopes can vary among alternative food sources, allowing for the identification of different trophic pathways or alternative food sources for a consumer.

Nitrogen Stable Isotopes Are Useful Tools for the Study of Food