The text discusses what types of morphological characteristics were used by early scientists to arrive at the phylogeny of animals. DNA sequence data have helped in the revision of phlyogenies of taxa within the larger groups
(i.e., bilaterians, sponges, cnidarians). Why are
characteristics like "fate of the blastopore" or "body symmetry" relatively good at predicting
larger-scale branching patterns on phylogenies?
A. The development of these characteristics
is controlled genetically, so similarities in
DNA sequence would be expected in more
closely related taxa.
B. Characteristics like those described are
necessary for living, so all organisms must
have those traits.
C. All animals are descended from a common
ancestor that had the traits described above.
D. The development of these characteristics
is controlled genetically, so DNA sequences
for important genes would be the same
between closely related taxa.
A
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What will be an ideal response?
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