Animal Kingdom Classification: Echinodermata and Chordata

Animal phyla delves into Echinodermata and Chordata. Echinoderms, exemplified by starfish, possess a unique water vascular system for locomotion and resource acquisition. Chordates, a distinct phylum, are defined by the presence of a notochord, a dorsal nerve cord, and pharyngeal gill slits – characteristics laying the groundwork for vertebrate evolution.

Phylum- Echinodermata

About: These animals have an endoskeleton of calcareous ossicles and, hence, the name Echinodermata.

• Features: All are marine with an organ-system level of organisation.
  • The most distinctive feature of echinoderms is the presence of a water vascular system which helps in locomotion, capture and transport of food and respiration.
  • An excretory system is absent.
• Example: Asterias (Starfish), Echinus (Sea urchin), Cucumaria (Sea cucumber).

Phylum- Chordata

About: Animals belonging to the phylum Chordata are fundamentally characterised by the presence of a notochord, a dorsal hollow nerve cord and paired pharyngeal gill slits.

• Classification: Phylum Chordata is divided into three subphyla: 
  • Urochordata or Tunicata 
  • Cephalo-chordata.
  • Vertebrata.

Comparison of Chordates and Non-chordates

Conclusion

Examining Echinodermata and Chordata reveals a spectrum of animal complexity. Echinoderms exhibit a specialized water vascular system, while chordates share defining features that pave the way for the development of vertebrates, the most intricate animal phylum.