[Campbell Biology P.509] According to Figure 21.17, which of the following statements about ... | Practice Question

According to Figure 21.17, which of the following statements about evolutionary divergence is correct?

  • A: Bacteria and Archaea diverged approximately 1 billion years ago.
  • B: Humans and chimpanzees diverged more recently than 10 million years ago.
  • C: The most recent common ancestor of all living things existed around 1 billion years ago.
  • D: Humans and mice diverged around the same time as humans and chimpanzees.

Explanation

Figure 21.17 consists of two parts. The upper tree shows the divergence of Bacteria, Archaea, and Eukarya, with the common ancestor existing before 4 billion years ago. The lower inset specifically details mammalian divergence. It clearly shows that humans and chimpanzees diverged approximately 6 million years ago, which is indeed more recent than 10 million years ago. In contrast, humans and mice diverged much earlier around 60-70 million years ago , and Bacteria/Archaea/Eukarya diverged in the billions of years ago range.