What two organisms did Darwin observe on the island? And explain what he noticed about each.

Tortoise Species

He realized that the tortoises had traits that allowed them to live in their particular environments. For example, tortoises that ate plants near the ground had rounded shells and shorter necks. Tortoises on islands with tall shrubs had longer necks and shells that bent upward, allowing them to stretch their necks

it's anything that aren't producers and consumers.

explanation:

you've got to be clear on what "this" is