B. Chordate features. Interpret the cladogram of chordates. I. Cladistic analysis. In contrast to the chordates, other animal phyla are characterized by solid nerve cords that are located either ventrally or laterally. Only abstract available online. Molecular Biology and Evolution 22 (11): 2275–2284. Animal Evolution and Diversity Evolution Q: ... For Questions 4–9, write the letter of the correct answer on the line at the left. 4. G. Adaptations to terrestrial existence. . Molecular Biology and Evolution 19: 762–776. D. Evolution of vertebrates from early chordates. In the deuterostome line (Fig. "Hemichordates, the phylum of bilateral animals closest to chordates, can illuminate the evolutionary origins of various chordate traits to determine whether these were already present in a shared ancestor (the deuterostome ancestor) or were evolved within the chordate line. (2005). In chordates, it is located dorsally (at the top of the animal) to the notochord. Evaluating Hypotheses of Deuterostome Phylogeny and Chordate Evolution with New LSU and SSU Ribosomal DNA Data. ↑ 31.0 31.1 31.2 Blair, J.E., and S. Blair Hedges, S.B. 1e, bottom left), a mouth forms dorsoanteriorly, and, during subsequent chordate evolution, body inversion results in a CNS that is dorsal to the gut. C. Chordate subphyla. E. Evolution of vertebrate classes. I got the PDF from the library. The nerve cord found in most chordate embryos develops into the brain and spinal cord, which comprise the central nervous system. F. Evolution of jaws. H. Endothermy. The first animals were tiny and soft-bodied, so ... 26.2 Chordate Evolution and Diversity Describe the most ancient chordates. Molecular Phylogeny and Divergence Times of Deuterostome Animals. . The two main phyla in the deuterostome line are the echinoderms and chordates; echinoderms have a spiny skeleton and a unique type of locomotion that utilizes a water vascular system and tube feet. Introduction to the Deuterostomia Your mouth comes second.