Phylum Chordata Phylum: Chordata

4 Characteristics of Chordates Defining Characteristics 1 Notochord. Found under the nerve chord. Runs down the dorsal side of an organism 2 3 4

4 Characteristics of Chordates Defining Characteristics 1 Notochord. Found under the nerve chord. Runs down the dorsal side of an organism 2 Dorsal Tubular nerve cord. Nerves arranged as a pipe filled with fliud 3 4

4 Characteristics of Chordates Defining Characteristics 1 Notochord. Found under the nerve chord. Runs down the dorsal side of an organism 2 Dorsal Tubular nerve cord. Nerves arranged as a pipe filled with fliud 3 Pharyngeal gill pouches (develop into gills in fish and amphibians and various other parts in reptiles to mammals (eg. Inner ear)) 4

4 Characteristics of Chordates Defining Characteristics 1 Notochord. Found under the nerve chord. Runs down the dorsal side of an organism 2 Dorsal Tubular nerve cord. Nerves arranged as a pipe filled with fliud 3 Pharyngeal gill pouches (develop into gills in fish and amphibians and various other parts in reptiles to mammals (eg. Inner ear)) 4 Muscular Postanal Tail (post = after anal = anus)

Subphylums of Chordata Characteristics Urochordata Larvae: Has all 4 characteristics of chordates Adult: Sessile, Lacks chordate characteristics with the exception of the pharyngeal pouches Cephalochordata Vertebrata

Subphylums of Chordata Characteristics Urochordata Larvae: Has all 4 characteristics of chordates Adult: Sessile, Lacks chordate characteristics with the exception of the pharyngeal pouches Cephalochordata Aquatic organisms containing all 4 characteristics of chordates as an adult Vertebrata

Subphylums of Chordata Characteristics Urochordata Larvae: Has all 4 characteristics of chordates Adult: Sessile, Lacks chordate characteristics with the exception of the pharyngeal pouches Cephalochordata Aquatic organisms containing all 4 characteristics of chordates as an adult Vertebrata Contain all 4 characteristics of chordates. The notochord, however, is replaced by vertebral column

Trends in Evolution of Chordates

Trends in Evolution of Chordates

Trends in Evolution of Chordates

Trends in Evolution of Chordates

Trends in Evolution of Chordates

Trends in Evolution of Chordates

Subphylum Vertebrata Class Osteicthyes: Most diverse class of vertebrate Fins Uses: Balance and Movement Two types of fins

Subphylum Vertebrata Class Osteicthyes: Most diverse class of vertebrate Fins Uses: Balance and Movement Two types of fins Ray-finned fishes: Thin fins supported by rigid ray structures 2) Lobe-finned fishes: fins are made of fleshy appendages. Later evolved into legs.

Characteristics of Ray-Finned Fish Bony Skeleton and scales Swim bladder (Air sac allows fish to hover in the water column) 2 chambered heart

Characteristics of Ray-Finned Fish Bony Skeleton and scales Swim bladder (Air sac allows fish to hover in the water column) 2 chambered heart Paired fins Jaws Gills

Class: Amphibia Amphibian: Live in land and water (Larval stage is aquatic, Adult stage is terrestrial) Common Examples: Frogs, Toads, Newts, Salamanders, Caecilians, Major Evolutionary Change:

Class: Amphibia Amphibian: Live in land and water (Larval stage is aquatic, Adult stage is terrestrial) Common Examples: Frogs, Toads, Newts, Salamanders, Caecilians, Major Evolutionary Change: Jointed Limbs that allowed the move to land

Characteristics of Amphibians Tetrapods (four legs) Undergo metamorphosis Three chambered heart Lungs in adults Smooth moist skin (Capable of gas exchange)