[Campbell Biology P.728] Referring to the "Visual Skills" section and the accompanying phylo... | Practice Question

Referring to the "Visual Skills" section and the accompanying phylogenetic tree diagram, what does the red-colored portion of the branch leading to "All other animals" represent?

  • A: The evolutionary lineage leading specifically to fungi, after diverging from animals.
  • B: The most recent common ancestor of all animals, including sponges.
  • C: The common ancestor shared by both fungi and animals, dating back 1 billion years ago.
  • D: The evolutionary lineage of animals that have true tissues and are not sponges, descending from a common animal ancestor.

Explanation

The diagram shows 'Sponges' branching off first from the 'Most recent common ancestor of animals 770 mya '. The red-colored branch then leads to 'All other animals'. The 'Tissues' section states that 'Sponges and a few other groups lack tissues. In all other animals, the embryo becomes layered during gastrulation'. Therefore, the red branch represents the lineage of animals that possess true tissues and undergo gastrulation, differentiating them from sponges.