Question

a pond becomes dry land. the graph shows changes in the abundances of certain types of living things as secondary succession occurs in the ecosystem.
secondary succession
changes in abundance
which line represents shade - tolerant seedlings?
a. line a
b. line b
c. line d
d. line e

Explanation:

Step1: Recall Secondary Succession

In secondary succession, early species (pioneers) are sun - loving, and later species (climax community - related) can be shade - tolerant. Shade - tolerant seedlings appear later as the ecosystem develops (more vegetation creates shade).

Step2: Analyze the Graph Lines

• Line A: Peaks early, likely a pioneer (sun - loving, early succession), not shade - tolerant.
• Line B: Peaks after A but still relatively early, not the latest.
• Line D: Peaks later than A and B but not the last.
• Line E: Increases over time and is the last to peak, representing the climax community - related species which are shade - tolerant as they grow in the shade created by earlier species.

Answer:

D. Line E