Ecological Succession & Biodiversity

Predict the natural event that would most likely cause succession in a grassy field.

• grass leaves injured by a frost

• grass is blown flat by a strong wind

• soil remains wet for several days after a heavy rain

• grass plants die after a long period of no rainfall

Identity an example of primary succession.

• tornado

• hurricane

• lava flow

• forest fire

Compare primary and secondary succession of an ecosystem.

• Primary succession is the sequence of plants that colonize a new area, while secondary succession is the sequence of animals that move once plant life is established.

• Primary succession is the sequence of species that become established early in a newly colonized area, while secondary succession is the sequence of species that move in much later.

• Primary succession is the establishment of a community in an area with no soil, while secondary succession is the establishment of a new community in an existing ecosystem that was disturbed by some catastrophic event.

• Primary succession is the establishment of a new community in an existing ecosystem that was disturbed, while secondary succession is the establishment of a community in an area that was altered due to fire.

If a tornado destroys a deciduous forest, describe the succession that will follow.

• classic ecosystem

• secondary succession

• climax community

• primary succession

Select the example that is NOT an impact that an invasive non-native species has on an ecosystem.

• change food webs

• increase biodiversity

• decrease biodiversity

• prey on native species

All but one of the factors may cause an animal species to be placed on the endangered list. Identify the factor that does NOT directly contribute to endangering an organism.

• pollution from human sources.

• habitat loss because of city construction.

• introduction of non-native animals to the range of the animal.

• introduction of the animal into places that it has previously gone extinct.

Complete this statement: If one species in a community dies out or moves, the community will _______________________.

• be affected.

• stop working.

• not be affected.

• replace the species

Identify the example that is NOT an invasive species.

• zebra mussels introduced into the Great Lake region from Russia that have affected the local species of mussels.

• tomato plants brought into a garden and given the opportunity to grow and thrive without any harm to any other plant species.

• the brown tree snake that was introduced to Guam from Australia and has led to the devastation of the local bird population.

• kudzu imported from China as a ornamental plant that has grown to cover native forests throughout the southeastern United States.

Explain how beaver dams contribute to species diversity in the ecosystem.

• provide a habitat for a variety of species

• provide access to food in winter

• ensure that only beavers have access to water

• keep predators away from the ecosystem

The Joshua Tree in the Mojave Desert: this is an example of a(n) __________ species that is confined to a certain region or having a comparatively restricted distribution.

• native

• umbrella

• endemic

• indicator