Deuterostomes and Chordates 1 BIOL 1407
Deuterostomes Phylum Echinodermata –Sea stars, sea urchins, sea cucumbers, crinoids Phylum Chordata –Tunicates, lancelets, fishes, amphibians, reptiles, birds, mammals
Phylum Echinodermata
Larvae: bilateral symmetry Adults: pentaradial symmetry Photo credit of pluteus larva: NOAA, 2001 Photo credit of adult brittle star: Larry Zetwoch, 1989, Florida Keys National Marine Sanctuary, NOAA
Water Vascular System Unique Hydraulic system used for feeding and locomotion Video of tube feet: atch?v=sMgfZj3DsXY&fea ture=related atch?v=sMgfZj3DsXY&fea ture=related Photo Credit: Dr. James P. McVey, NOAA Sea Grant Program
Phylum Chordata
Characteristics of Chordates Bilateral symmetry Triploblastic Coelomate Segmented
Other Chordate Characteristics Complete Digestive System Closed Circulatory System Respiratory System: Gills or Lungs Excretory System: Kidneys Centralized Nervous System
Unique Chordate Characteristics
Phylum Cephalochordata: Lancelets
Phylum Urochordata: Tunicates
Major Chordate Clades Craniates: Cranium –Vertebrates + Hagfishes Vertebrates: Vertebral Column –Gnathostomes: Jaws & Paired Appendages –Osteichthyans: Lung/Lung Derivatives –Lobe-finned Fishes: Limb Bone Pattern –Tetrapods: Four Well-Developed Limbs –Amniotes: Amniotic Egg
Hagfishes Craniates Head Simple cranium Not vertebrates
Characteristics of Vertebrates Vertebral Column Well- developed skull Photo Credit of Hippo skull: Raul654, 2005, Wikimedia Commons
Photo Credit for Platypus Skeleton at Melbourne Museum: Peter Halasz, 2006, Wikimedia Commons
Lampreys Vertebrates No jaws or paired appendages
Evolution of Jaws
Chondrichthyes Cartilaginous skeleton Jaws Present Paired Appendages
Osteichthyans Bony Skeleton Lung and Lung Derivatives Two Main Groups: –Ray-finned –Lobe-finned
Ray-Finned Fishes Fins are supported by fin rays Swim bladders Largest vertebrate group
Lobe-Finned Vertebrates Fins and limbs supported by internal bones and muscles
Photo Credit: Courtesy of Dennis Murphy, Devonian Times, Lobe-Fin Pattern
Video of Fish with Fingers:
The End Unless otherwise specified, all images in this presentation came from: Campbell, et al Biology, 8 th ed. Pearson Benjamin Cummings.