Which statement best describes how ecological succession proceeds in a new environment?

• A. It begins with complex communities forming immediately.
• B. It starts with simple organisms and progressively becomes more complex.
• C. It remains static after initial colonization.
• D. It is driven only by climate, not organisms.

Answer: (B)

Ecological succession in a new environment describes how communities build up gradually from simple to more complex forms. In primary succession, colonizers begin with organisms that tolerate harsh conditions and can reproduce quickly, like lichens and mosses. These pioneers break down rock and add organic material, slowly forming soil. As soil develops, it retains water and nutrients better, allowing larger and more diverse plants to take root, followed by shrubs and eventually trees. With each stage, the ecosystem supports more species and more intricate interactions, so the overall community becomes increasingly complex over time. An immediate complex community is unlikely because soil formation and ecological interactions take time. The system does not remain static after colonization, and climate isn’t the only driver—organisms themselves modify the environment and steer which species can establish.