Post on 19-Dec-2015
Animal Diversity 3Deuterostomes: Echinodermata and Chordata
Echinodermata & Chordata
Echinodermata “Spiny skin”
• Endoskeleton of spiny plates
• Marine animals (no freshwater or terrestrial species)
• Adults = radial; larvae = bilateral
• Water vascular system (used for feeding, gas exchange, and locomotion)
• Canals end in “tube feet”; opening = madreporite
Bilateral Larva
Chordata
•Pharyngeal slits/pouches
•Dorsal nerve cord
•Notochord
•Post-anal tail
Pharyngeal slits
Dorsal (hollow) nerve cord
Nerve cord
Notochord
(versus solid, ventral nerve cord)
Notochord
Nerve cord
Notochord
Flexible rod that supports the nerve cord(becomes intervertebral discs in between vertebrae in humans.)
Post anal tail
(body extends past the anus...)
Chordata
•Pharyngeal slits/pouches
•Dorsal nerve cord
•Notochord
•Post-anal tail
Subphyla
Tunicata(once called Urochordata)Craniata
Cephalochordata
CephalochordataExample: lancelets
Tunicata
Craniata (Vertebrata)
Specimens today•Lancelet (one per table)
•Lamprey
•Sea cucumber
•Sea Urchin
•Sea Star