WebAnswer: This is one of the classic hard problems in evolution. How is it possible that a species evolved into animals as different as starfish and people? Echinoderm is the group … WebAbstract. ONE of the difficulties in an account of the origin of the echinoderms is their five-fold radial symmetry. Nichols 1 has proposed a hypothetical ancestral echinoderm …
Origin of Echinodermata SpringerLink
WebMar 11, 2024 · Echinoderms, or members of the phylum Echinodermata, are some of the most easily-recognized marine invertebrates. This phylum includes sea stars (starfish), sand dollars, and urchins, and they are … WebMay 11, 2024 · The latest common ancestor of deuterostomes is therefore hypothesized to have possessed pharyngeal openings, which were lost along the branch leading to extant … lappi metsätilat
15.5 Echinoderms and Chordates - Concepts of Biology - OpenStax
WebThe phylum Echinodermata is subdivided into clades/classes that are generally differentiated by the geometry of the body, symmetry of the body, presence or absence of … Web2. Five-part radial symmetry. All echinoderms are bilaterally sym-metrical as larvae. During their development into adults, the larvae’s body plan becomes radially symmetrical. Most … WebDec 15, 2024 · Figure 4.5. 1: Phylogenetic tree of life: A phylogenetic tree of life, showing the relationship between species whose genomes had been sequenced as of 2006. The very center represents the last universal ancestor of all life on earth. The different colors represent the three domains of life: pink represents eukaryota (animals, plants, and fungi ... lappi matkailukohteet