1. CH 31 Part 1- Outline Chordates Non-vertebrate Chordates Vertebrates
Subphyum Cephalochordata
Subphylum Urochordata
Vertebrates
Fishes
Amphibians
Reptiles
Birds
Mammals

2. Animal Evolution 2
3.5 Billion years ago first life on Earth 350 (or so) million years ago first tetrapods appear 230 million years ago first mammals appear 100,000 years ago modern humans

3. 3
Animal Evolution

4. Pg 560a
You should be able to completely fill out this chart (on the right) and the chart for chordates by the end of chapter 31.
What differentiates chordates from echinoderms?
What is a deuterostome again?

5. Phylum Chordata Four Main Characteristics Chordates Notochord
A dorsal supporting rod
Nerve Cord
Dorsal tubular nerve cord
Anterior portion becomes brain

6. Phylum Chordata Four Main Characteristics Chordates 6
Pharyngeal Pouches
Only seen in embryonic development
Tail
In embryo if not seen in adult

7. Pg 560b

8. Invertebrate Chordates
Notochord persists and is never replaced by a vertebral column
(Subphylum Cephalochordata) - Lancelets
lancelets
(Subphylum Urochordata) - Tunicates
sea squirts

9. Pg 560c

10. Figure 31.1a

11. Figure 31.1b
How are these animals different from other vertebrates you are familiar with (fish, amphibians, etc.)??

12. Figure 31.2 - Sea squirt, Halocynthia

13. Sea Squirt Feeding Video!!
Sea Squit 13
Sea Squirt Feeding Video!!

14. Sea Salps 14
Sea Salps Video!!

15. Vertebrates Subphylum Vertebrata
Internal jointed skeleton of vertebrates is living tissue that grows with the animal
Main axis of skeleton consists of vertebral columns and a skull that encloses the brain
Cephalization is accompanied by sense organs
Evolution of jaws and predation
Amnion allows reproduction on land

16. Phylogenetic Tree of the Chordates

17. Phylogenetic Tree of the Chordates

18. Vertebrate Features
Living endoskeleton with vertebral column
Closed circulatory system
Paired appendages
Efficient respiration and excretion
High degree of cephalization
Adapted to active lifestyles
How have these features allowed vertebrates to grow so large compared with the invertebrates?