Mild grazing of plants by herbivores:

$A$ plant growing on another plant without drawing any nourishment is

$A$: Five closely related species of warblers living on the same tree can avoid competition and co-exist.
$R$: This occurs due to behavioural differences in their foraging activities.

What is the term for an interaction where both organisms benefit and are essential for each other's survival?

Identify the figure given below.

Birds living in the same habitat generally differ in their niches because they . . . . . . .