Chapter 22: Evolution - Natural Selection and Descent with Modification

Flashcards covering key concepts from Chapter 22 on natural selection, descent with modification, antibiotic resistance, whale limb evolution, and human-chimp DNA similarities.

Which of the following is not an observation or inference on which natural selection is based?

B) Poorly adapted individuals never produce offspring.

Which observation helped Darwin shape his concept of descent with modification?

D) South American temperate plants are more similar to the tropical plants of South America than to the temperate plants of Europe.

Within six months of effectively using methicillin to treat S. aureus infections in a community, all new S. aureus infections were caused by MRSA. How can this best be explained?

C) Some drug-resistant bacteria were present at the start of treatment, and natural selection increased their frequency.

The upper forelimbs of humans and bats have fairly similar skeletal structures, whereas the corresponding bones in whales have very different shapes and proportions. However, genetic data suggest that all three kinds of organisms diverged from a common ancestor at about the same time. Which of the following is the most likely explanation for these data?

B) Natural selection in an aquatic environment resulted in significant changes to whale forelimb anatomy.

DNA sequences in many human genes are very similar to the sequences of corresponding genes in chimpanzees. The most likely explanation for this result is that

A) humans and chimpanzees share a relatively recent common ancestor.