[Campbell Biology P.731] According to the 'The Diversification of Animals' section, which of... | Practice Question

According to the 'The Diversification of Animals' section, which of the following statements about animal phylogeny are currently supported by scientific evidence? Select all that apply

  • A: All extant and extinct animal lineages are monophyletic, forming a clade called Metazoa.
  • B: Sponges (phylum Porifera) are considered basal animals that diverged early in the history of the animal group.
  • C: Evolutionary relationships among animal phyla are primarily inferred using only morphological traits.
  • D: There are only 15 recognized extant animal phyla today.

Explanation

The section 'The Diversification of Animals' explicitly states two key points: 1 All animals share a common ancestor, forming the monophyletic clade Metazoa. 2 Sponges are the basal sister group to all other animals. It also mentions using multiple types of data not just morphological traits and notes 'about three dozen phyla' are recognized, with 15 shown in a figure.