Primary and Secondary Succession

Ecological Succession Ecosystems are constantly changing in response to natural and human disturbances. As an ecosystem changes, older inhabitants gradually die out and new organisms move in, causing further changes in the community.

Primary Succession Occurs on new lands where no soil exists The first species to populate the area are called pioneer species. Picture shows plant growth on new lava

Secondary Succession When a disturbance of some kind changes an existing community without removing the soil Examples: wildfires burn woodlands

The four pictures show succession in a small area in New York. 1.) In which stage is grass mostly found? 2.) The grasshopper sparrow is so named because of what it eats. Why do you think it is mostly found in stage 1? 3.) What new species appears in Stage 3? What can you hypothesize about this species based on the four pictures? 4.) By Stage 4, what type of vegetation has taken over? 5.) How did the trees change the environment, making it less favorable for the grasses to grow? 6.) Which animal survived in all stages of this succession? Why?

Environmental Change and How it Impacts Ecosystem Stability In your groups research your assigned topic. What happened? In which biome did the even occur? How did it effect the environment? How has the environment changed as a result of the dynamic environmental change? Include information on succession. Provide a 3 minute presentation for the class. Every member must speak!