Question

49 cetaceans are whales and their relatives. the diagram shows some fossils of cetaceans. fossils of some cetaceans oldest ambulocetus natans rodhocetus balochistanensis basilosaurus isis youngest which statement provides the best evidence that ambulocetus natans is an ancestor of basilosaurus isis? a homologous structures occur in each fossil. b similar nitrogenous bases are found in the dna of each fossil. c the fossils were found in different locations. d the youngest fossil is larger than the older fossils. 25 zoogeographic 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. zoogeographic regions key geographical barriers such as mountains or bodies of water the similarities of organisms in which two areas numbered above provide the best evidence for common ancestry between the organisms in both locations? a 1 and 2 b 3 and 4 c 5 and 6 d 7 and 8

Explanation:

1. For the first question about cetacean fossils, homologous structures in fossils are strong evidence of an evolutionary relationship and common - ancestry. Homologous structures have a similar anatomical origin, which implies that the organisms sharing them are related through a common ancestor.
2. For the second question about zoogeographic regions, areas that are closer geographically and have fewer geographical barriers are more likely to have organisms with a common ancestry. Areas 5 and 6 are adjacent and separated by relatively less - significant barriers compared to other pairs, suggesting a higher probability of common ancestry among their organisms.

Answer:

1. A. Homologous structures occur in each fossil.
2. C. 5 and 6