Phylum Chordata
The Chordates!
All chordates have these 4
characteristics:
1. Dorsal Hollow Nerve Cord: a nerve cord
that runs along the back
2. Notochord: long, supporting rod that runs
below the DHNC
3. Pharyngeal Pouches: slits in the throat that
may help with gas exchange in some animals
4. Post-Anal Tail: at some point in their lives,
all chordates have a tail that extends past the
anus
Most chordates are vertebrates but there are
some non-vertebrate chordates.
The two groups of non-vertebrate chordates (chordates
without backbones) are:
Tunicates (sea squirts)
Lancelets
•Filter feeders that live in the ocean
•Small, fish-like creatures
that live on the ocean floor
•Soft-bodied
•Show all the characteristics of
chordates as LARVAE
SO… Phylum Chordata includes:
3 subphyla:
Subphylum Urochordata (tunicates)
Subphylum Cephalochordata (lancelets)
Subphylum Vertebrata (vertebrates)
Vertebrates: fishes, amphibians, reptiles,
birds, and mammals
Vertebrates include: fishes, amphibians,
reptiles, birds, and mammals
All vertebrates have:
– A backbone
– Bilateral symmetry
– Endoskeletons
– Closed circulatory systems
– Complex brains & sensory organs
– Efficient respiratory systems