Deuterostomes and Chordates 1 BIOL 1407. Deuterostomes Phylum Echinodermata –Sea stars, sea urchins, sea cucumbers, crinoids Phylum Chordata –Tunicates,

Deuterostomes andChordates 1

BIOL 1407

Deuterostomes

• Phylum Echinodermata– Sea stars, sea urchins, sea cucumbers,

crinoids

• Phylum Chordata– Tunicates, lancelets, fishes, amphibians,

reptiles, birds, mammals

Phylum Echinodermata

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: http://www.youtube.com/watch?v=sMgfZj3DsXY&feature=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, http://www.devoniantimes.org/opportunity/tetrapodsAnswer.html

Lobe-Fin Pattern

• Video of Fish with Fingers: http://www.pbs.org/wgbh/evolution/library/03/4/l_034_03.html

The End

Unless otherwise specified, all images in this presentation came from:

Campbell, et al. 2008. Biology, 8th ed. Pearson Benjamin Cummings.