What defining set of characteristics must an organism possess at some life stage to be classified within the Phylum Chordata?
Answer
A notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail.
Membership in the Phylum Chordata is defined by the presence of four specific anatomical features at some point during the organism's life cycle. These features are the notochord, which provides skeletal support; a dorsal hollow nerve cord, which develops into the central nervous system; pharyngeal slits, which are involved in filter-feeding or respiration; and a post-anal tail, extending beyond the anus. For birds like the Willow Flycatcher, these features are manifest during their embryonic development, eventually culminating in the complex vertebral structure characteristic of vertebrates.
Related Questions
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