Question

read the text.
when non - native species are introduced into new areas, the consequences often include widespread disruption of the native ecosystem. this has happened repeatedly in australia, where native species evolved in an isolated environment. in the 1920s, several thousand camels were released into the australian outback. originally imported to do work, the camels werent needed once gasoline engines arrived. because they have no natural predators in australia, the number of now - wild camels has increased to over a million. the australian camel herd is now the largest on earth. these camels drink large amounts of water, thus exhausting water holes important to native populations. they also eat so many plants that they leave insufficient food for native birds and reptiles. the native ecosystem simply cant cope with the camels.
which organizational structure does this text primarily use?
cause - effect
problem - solution

Explanation:

The text first presents the cause (introduction of non - native camels to Australia) and then describes the effects (disruption of native ecosystem, camel population growth, depletion of water and food for natives). It doesn't offer a solution, so the structure is cause - effect.

Answer:

cause - effect