Which statement describes thylakoids?

density independent

Explanation:

In Ecology, a limiting factor refers to an environmental condition that hinders the growth and distribution of organisms in an ECOSYSTEM. A limiting factor hinders or hampers the productivity of an organism in its habitat.

There are two major types of limiting factors that affect organisms in their ecosystem viz: density dependent and density independent limiting factors. Density independent factor limits the size of a population independently of how dense the ecosystem's population is. This means that density independent factor affects a population irrespective of its size. Example of density independent factor are natural disasters e.g earthquake, hurricane, forest fire as mentioned in the question.

In this question, both populations of trees and birds are affected irrespective of the size of the ecosystem's population.