Question

During ecological succession

 (a) the gradual and predictable change in species composition occurs in a given area 

 (b) the establishment of a new biotic community is very fast in its primary phase 

 (c) the numbers and types of animals remain constant 

 (d) the changes lead to a community that is in near equilibrium with the environment and is called pioneer community.

Answer 1

Correct option (a) the gradual and predictable change in species composition occurs in a given area 

Explanation:

Tine gradual and fairly predictable change in the species composition of a given area is called ecological succession. During succession some species colonise an area and their populations become more numerous, whereas populations of other species decline and even disappear.