6. Th e fact that there was never a land bridge between Australia and mainland Asia is evidenced by the fact that the animal species in the two areas are very diff erent. Asian placental mammals and Australian marsupial mammals have not been in contact in the last several million years.

Each of the following passages contains a single argument. Using the letters “P”

and “C,” identify the premises and conclusion of each argument, writing premises fi rst and conclusion last. List the premises in the order in which they make the most sense (usually the order in which they occur), and write both premises and conclusion in the form of separate declarative sentences. Indicator words may be eliminated once premises and conclusion have been appropriately labeled. Th e exercises marked with a star are answered in the back of the book.