Answer:
Size
Explanation:
We can define niche as particular place where certain things exist. This is a very broad term and it can refer to a particular workplace for a particular society or it can be referred to as a specific role taken by an organism in a certain community.
If we talk about ecological niches they can be either fundamental niche or realized one. Both describe how organisms living in a particular zone interact with their environment and community, however, the difference between both is their size.
Fundamental niche cover all the conditions which a specific organisms need for its survival like temperature, precipitation, sunlight, food etc.
However, Realized niche covers only those conditions which are in actual used by a specific organisms while interacting with other organisms. For example: Competition for food and resources, predation to get food etc.
Therefore, it is quite evident that Fundamental niche is larger in size than realized niche.
Hope it help!
