Question

scientists have been interested in the evolutionary history of whales for a long time. in the chapter story, several types of evidence were used to explore the connections between modern whales and their early relatives. for example, a collection of fossil bones collected by indian researcher ranga rao provided important information to help shed light on whale relationships. match each of the six types of evolutionary evidence outlined in the book to the specific examples of evidence for the evolutionary relationships among aquatic mammals.

Answer 1

Fossils and anatomical structures provide evidence for the evolutionary history of whales, highlighting their terrestrial ancestry and subsequent adaptations for aquatic life. Vestigial structures and homologies are key areas of study for understanding their phylogeny.

Step-by-step explanation:

Scientists have used various types of evidence to trace the evolutionary history of aquatic mammals, particularly whales. One pivotal piece of evidence comes from the structure of fossilized bones, which allows scientists to see the progression and transition of species over time. The fossil record, including that of well-known ancestors of modern whales like Pakicetus and Rodhocetus, has been instrumental in piecing together these evolutionary relationships. Rodhocetus, with its unique type of ankle bone typically found in land animals, offers evidence that modern whales evolved from land-dwelling ancestors.

Another evidence type is anatomy and embryology, which examines homologous structures across different species. For example, the similar construction of the bones in the appendages of a human, dog, bird, and whale points to a common ancestor. Additionally, the concept of vestigial structures, like the presence of traces of pelvic bones in whales, supports the theory that these aquatic creatures evolved from organisms that had hindlimbs.

Together, these evidences contribute to our understanding of animal phylogeny and help scientists construct phylogenetic evolutionary tree diagrams, showcasing the morphological and genetic relationships between species and their shared evolutionary paths.

Answer 2

Scientists have used fossils and anatomy to explore the evolutionary history of whales and their relatives. Fossil evidence shows the progression of form over time, and homologous structures indicate shared ancestry among different organisms. The discovery of unique bones in aquatic mammals further supports evolutionary relationships.

Step-by-step explanation:

Scientists have used various types of evidence to explore the connections between modern whales and their early relatives. One type of evidence is fossils, which provide solid proof of evolution and show the progression of form over millions of years. For example, the fossil record of whale flipper bones shares a similar morphology with bird and mammal appendages, indicating a common ancestor.

Another type of evidence is anatomy and embryology. Homologous structures, such as the bones in the appendages of humans, dogs, birds, and whales, show the same overall construction due to their origin in a common ancestor. This similarity in structure points to evolutionary relationships among these organisms.

Additionally, the fossil record provides evidence for the evolutionary relationships among aquatic mammals. For example, the discovery of an ankle bone in Rodhocetus, an aquatic mammal related to whales, which is otherwise unique to a group of land animals, indicates a connection between aquatic and land-dwelling species.