1. (coelomates = second mouth)
Deuterostomes
(coelomates = second mouth)

2. Phylum Echinodermata Sea cucmbers Sea stars Sea urchins brittle stars
Feather stars
Sea stars
brittle stars
Sand dollars

3. Echinoderm Deuterostome Traits
1.Coelom
2. mouth forms second
2. Bilaterally symmetrical larvae
But all adults have radial symmetry
3. Complete digestive system
(alimentary canal)

4. Retro traits : bringing back the past
Regeneration ability
Radial symmetry: works great for sessile
Seems to work for slow moving creatures too
Only larvae still bilateral (evidence of a bilateral ancestor)
No head or brain
Sensory receptors and nerves spread out in a network around the body
No respiratory, circulatory or excretory system
Diffusion through tube feet

5. Echinoderm Derived Traits
Endoskeleton of hard spiny plates
Covered by thin layer of epidermis
Tube feet (100s of suction cup feet)

6. Sea Star Feeding Sea star pulls a bivalve open using its tube feet
Sea star everts its stomach into the bivalve shell and digests the meat inside
Stomach returns to interior of sea star

7. Phylum Chordata All are deuterostome coelomates
All have bilateral symmetry at some stage of their life

8. 4 key Chordate Characteristics
Dorsal hollow nerve cord
A notochord (skeletal rod) supports the nerve cord at some point in development
Pharyngeal pouches at some point
Post anal tail at some point

10. Phylum Chordata Superclass : Agnatha – jawless fish
2 classes: hagfish & lamprey
Superclass: Gnathostomata – jaw mouth
classes: chondrichthyes,
osteichthyes,
Amphibia,
Reptilia,
Aves,
Mammalia

11. Primitive Craniates= Superclass Agnatha
(jawless fish)
Hagfish
Lampreys
Ostracoderms
(extinct silurian fish)
Armor plated

13. Superclass Gnathostomata
Jaw mouth = all have jaws
Advantage: break shells/armor/exoskeletons, bite off pieces
Includes All other fish
(not hagfish or lamprey)
All tetrapods
(gnathostomes that have 4 limbs)

14. Class Chondrichthyes Cartilaginous Fish Sharks Skates Rays Traits
No swim bladder
No operculum (must swim to breath)

15. Class Osteichthyes – bony fish
Have bone skeleton
Most have swim bladder
Have operculum over gills

16. Lobe-finned fish developed supportive fins & simple lungs from swim bladder

18. Class Amphibia = first Vert. on land
Fish like traits:
1. Eggs & larvae in water
2. Larval respiration gills/skin
3. Larval circulatory system like
a fish
2 chambered heart
single loop circulatory system

19. Class Amphibia 3 Orders of Amphibian 1. frogs/toads
2. salamanders/newts
3. caecilians

20. Adults move onto land so need..
Stronger skeletal system (no buoyancy)
Respiration by lungs/skin
New type of circulatory system
3 chamber heart
2 loop circulatory system
Faster, more efficient
Evolutionary Advantage to land
No predators
Insects for food

22. Class Reptilia Amniote egg = freedom from water
Shelled egg = internal fertilization
Scales = prevent dehydration
no O2 from diffusion any longer
Lungs developed folds and pouches
Increased surface area
Heart begins to divide into 4 chambers in crocodilians

23. Reptiles….

24. Class Aves = Birds Amniote eggs Feathers & scales
Flight: light bones, flight feathers,
Endothermic: high metabolism=high energy
Lungs with air pockets – always fresh air
4 chambered heart – no mixing of oxygenated and un-oxygenated blood

26. Class Mammalia Fur/hair & subcutaneous fat Endothermic
Produce milk (mammary glands)
All have amniotic membrane but not all are contained in an egg

27. Mammal Amniotes Amniotes of 3 types Monotremes lay eggs
Marsupials babies are born as immature embryos and finish development in pouch
Placental mammals embryos obtain nutrients from their mother through a placenta. Offspring are much more mature when born

28. Amnion membranes

29. Amniotes diverged quickly
1) synapsids evolved into therapsids and then into mammals
2) Sauropsids evolved into Diapsids which then branched into reptiles, dinosaurs and birds