Tiny free-living animals on the surface of water constitute:

The rule which states that mammals from colder climates generally have shorter ears and limbs to minimize heat loss is known as:

Phenotypic variants formed in a population due to change in environment are called

How many of the following statements are correct about niche?
$i$. It denotes the functional role played by an organism.
$ii$. It deals with the flow of energy from one organism to another.
$iii$. As soon as a niche is left vacant,other organisms fill that position.
$iv$. The same niche is shared by two or more species.
$v$. Organisms living in the same habitat differ in their niches.

Which one of the following pairs is mismatched?

What is formed by the populations of different species living together in a common habitat?