Non-Chrodates (Introduction)
- Non-chordates, also known as invertebrates.
- Non-chordates are animals that do not possess a notochord (which is a flexible rod-like structure found in the embryonic stage of chordates which are animals with backbones).
- Non-chordates make up the vast majority of the animal kingdom and exhibit an incredible diversity of body forms and adaptations.
- Non-chordates include numerous phyla such as - Porifera (sponges), Cnidaria (jellyfish, corals), Platyhelminthes, Annelida (earthworms, leeches), Arthropoda (insects, spiders, crustaceans), Mollusca (snails, clams, octopuses), Echinodermata (sea stars, sea urchins).
- These animals exhibit various levels of complexity in terms of body organisation, locomotion, reproduction, and feeding strategies.
- While non-chordates lack a notochord, they often possess other structural elements and systems that provide support and locomotion.
- For example, arthropods have an exoskeleton, mollusks have a muscular foot, and annelids have a hydrostatic skeleton.
- Each phylum within the non-chordates has its own unique characteristics and adaptations that have allowed them to live in diverse habitats around the world.