If eras are marked by major changes in life forms, what distinguishes one period from the next

19. scientists use meteorites that hit earth to provide evidence of the composition of earth's interior because they hypothesize that

Amale bird-of-paradise uses a dance to attract mates in which it flaps its tail feathers on the ground and jumps around a potential female mate. a different male bird-of-paradise does a similar dance but it jumps around the female in the opposite direction. the female bird is only attracted to one style of dance, in one direction. this is an example of speciation.

Zoo geographic regions are characterized by the presence of specific groups of animals these regions are determined by the taxonomic or phylogenetic relationships of animals. the map shows the zoogeographic regions proposed by the naturalist alfred russel wallace in 1876. the similarities of organisms in which two areas numbered above provide the best evidence for common ancestry between the organisms in both locations ?