Climax communities are communities that are undergoing primary succession

A climax community is a stable group of plants and animals that have reached the end result of the succession process. I hope this was what you were looking for.

Climax community is an ecological community that has reached the final stage of ecological succession. At this point bio-diversity is maximum and no further changes take place. It is the most stable period

Explanation:

it will increase due to the time span

your answer is "the 1950's"