Autogenic succession is driven by changes within the ecosystem, such as soil changes or shading by plants.

• A. It is driven by climate change
• B. It is driven by external disturbances
• C. It is driven by changes within the ecosystem, such as soil changes or shading
• D. It is random

Answer: (C)

Autogenic succession is driven by changes that originate inside the ecosystem. As plants grow, they alter their environment through processes like developing soil, accumulating organic matter, and creating shade that changes light, temperature, and moisture at the ground level. These internal changes build a feedback loop: new conditions favor different species, which in turn further modify the environment, guiding the community from early pioneers toward more complex, stable assemblages. That internal, plant- and soil-driven transformation is what the statement describes.

External factors, such as climate shifts or disturbances like fire or logging, act from outside the local community, even though they can influence the trajectory of succession. Randomness doesn’t reliably produce the orderly, progressive change seen in autogenic succession.