A sedentary sea anemone gets attached to the shell lining of hermit crab. The association 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.

Give differences: Commensalism and Mutualism.

Association between suckerfish $ (Remora) $ and shark is

A cokoo laying eggs in the nest of other species of birds is an example of