Phylum Echinodermata
Echinodermata, the largest phylum to lack any freshwater and land representatives, includes certain marine animals found at every ocean level, such as starfish, sea urchins, and sea cucumbers, and are usually recognizable by their five-point radial symmetry. Coming from a common ancestor, most echinoderms hold the distinct trait of tissue regeneration. Methods of reproduction vary among the current 7,000 species of the phylum; some reproduce asexually and some, sexually. During embryo development, echinoderms develop similarly to chordates until metamorphosis, which causes the loss of bilateral symmetry and causes the phylum's radial symmetry. Now that we know some things about echinoderms, below are certain species of the phylum and their reproductive systems.
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