Why is it necessary to see a similar pattern of change in fossils from several places in order to conclude that an extinction happened?

Which country is the smallest island of the greater antilles

Canada plays an important role in the global community in all of the following ways except by a. acting as a superpower with influence over europe and asia. b. promoting arms control and disarmament. c. working with the commonwealth of nations to promote trade. d. promoting trade with japan and other asian countries.

In the following diagram, four different index fossils are labeled: which of the labeled fossils comes from the oldest organism? a b c d