What is the effect of a parasite on the host?

Explain sexual deceit.

Flamingos and fish compete in a lake for .......... .

Statements
$I.$ Recent studies support competition as suggested in 'Gause's Competitive Exclusion Principle'.
$II.$ Gause's hypothesis states that if two species compete for the same resources,then one will be eliminated by the other species.
$III.$ More recent studies point out that species facing competition might evolve mechanisms that promote co-existence rather than exclusion.
$IV.$ Gause's competitive exclusion principle is effective when resources are in excess.
$V.$ Unlimited resources give better opportunity for adaptation.
Choose the correct combination of statements.

Explain commensalism with the example of an egret and cattle.

All the following interactions are mutualism,except