Concept explainers
To determine: The group or groups in which bilateral symmetry would expect to occur if it were to evolve among cnidarians.
Introduction: Animal phylogeny is a rapidly changing field for the biologists. Even if the members of animal kingdom are incredibly diverse, there are various animals sharing certain features that are similar to that of other organisms of the kingdom.
Explanation of Solution
If bilateral symmetry were to evolve among cnidarians, it would expect to develop among the groups of non-sessile, mobile cnidarians, such as jellyfish.
To explain: The reason why if bilateral symmetry were to evolve among cnidarians, it would expect to develop among the groups of non-sessile, mobile cnidarians.
Introduction: Animal phylogeny is a rapidly changing field for the biologists. Even if the members of animal kingdom are incredibly diverse, there are various animals sharing certain features that are similar to that of other organisms of the kingdom.
Explanation of Solution
Phylum Cnidaria comprises approximately 9000 species. It includes hydra, jellyfish, sea anemones, corals, and so on. The body is composed of only two layers of cells. The body exhibits radial symmetry. Bilateral symmetry is particularly advantageous in non-sessile animals. This is because the adaptive advantages of bilateral symmetry are to develop a head along the anteroposterior axis. Thus, it would be expected to develop among the groups of non-sessile, mobile cnidarians.
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Chapter 7 Solutions
MARINE BIOLOGY
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