Question

In Australia, millions of nonnative cattle produce a huge amount of dung. For decades, Australia has imported nonnative dung beetles to help clean up the dung. Which sentence best explains why native Australian dung beetles were not doing the job?

A. Cow dung is not part of any native Australian species' niche.
B. Native Australian dung beetles lack a niche in Australia.
C. Cows have no known niche in Australia.
D. Decomposers lack a native niche in Australia.

Answer 1

The sentence that best explains why the native Australian dung beetles were not doing the job is "Cow dung is not part of any native Australian species niche." The beetles in Australia had formed alongside the kangaroos and wombats. When the cattle were brought to Australia in the 1880's by European settlers, the beetles were not used to the texture of the dung. It was much different and the dung was not decomposing. Native beetles were not using this dung as a feeding source. This left the cattle not feeding in the pasture because they won't eat near the dung. This reduced the cattle grazing land.