Chapter 23: Chordates

What does the phylum Chordata consist of?

Every vertebrate

What type of development do all vertebrates have?

Deuterostomes

Which phyletic group/outgroup is phylum Chordata in?

Monophyletic group

Cambrian explosion

Explosion 541 million years ago where most animal phyla evolved

Name the first vertebrate & its species to evolve and when.

Fish, specifically Haikouella lanceolata 530 million years ago

Where did all life begin?

The water

Species Radiation

Lots of species quickly evolving

5 Requirements to be a Chordate

Notochord

Nerve Chord

Pharyngeal Pouch

Postanal Tail

Endostyle (Thyroid)

Notochord

Flexible rod that gives structure

Nerve Chord

Collection of nerves running down the body

Pharyngeal Pouch

Pouches that become different things during development

Postanal Tail

Tail after the anus

Endostyle (Thyroid)

Regulates hormones

What percentage of animals are vertebrates?

3%

Which kingdom does the Chordata phyla belong to?

Animalia

3 Subphylum of Chordata

Tunicata/Scalps/Seasquirts

Cephalochordata (Lancets)

Vertebrata/Craniate

Tunicata/Scalps/Seasquirts

Lost their tails during metamorphism & scalps are colonial organisms

Cephalochordata (Lancets)

Small eel like animal with all the requirements to be a chordate

Colonial Organisms

Individuals grouping together to form a bigger organisms

Ex: Lancets

4 requirements to be a Vertebrata/Craniate

Have a cranium

Cephalization

Endoskeleton

Different organ systems

Cranium

Protective covering for the brain

Endoskeleton

Skeleton inside the body

Ex: Mammals

Cephalization

Having a head

Head

Where sensory and nervous organs are found

Haikouella lanceolata

First vertebrate

5 Types of Vertebrates

Fish

Reptiles

Amphibians

Birds

Mammals

What percentage of vertebrates are fish?

50%

Extant

living

Name and define the 2 types of fish

Agnatha: Jawless vertebrates (Hagfish & Lamprey)

Gnathostomes: Jawed vertebrate (Placoderm)

Which type of vertebrate are most fish?

Gnathostomes

Placoderm

First jawed vertebrate

Which animal is in the subphyla Cephalochordata?

Lancets