6 Chordates

5 Characteristics shared by ALL Chordates

1.Dorsal hollow nerve chord

Hollow tube derived from ectoderm

5 Characteristics shared by ALL Chordates

2.Post anal tail

tail that extends beyond the anus

5 Characteristics shared by ALL Chordates

3.Pharyngeal slits

Opening of the Pharynx that extend to the
outside environment

5 Characteristics shared by ALL Chordates

4.Notochord

Flexible rod-shaped structure located between the digestive tube and the nerve chord

5 Characteristics shared by ALL Chordates

5.Endostyle/Thyroid gland

considered an evolutionary precursor of the vertebrate thyroid gland; longitudinal, ciliated groove found in the pharynx of non-vertebrate chordates

Cephalochordates (Lancelets)

Notochord extends into the head. There is no well-defined brain and nervous system is very simple. Usually found buried in sand
at the bottom of tropical seas

Urochordates (Tunicates)

Adults lack a notochord, dorsal hollow nerve chord or post-anal tail. Bodies are made of tunic

Tunic

a cellulose-like material that covers their outer body

Cranium

a bony, cartilaginous, or fibrous structure surrounding the brain, jaw, and facial bones

Craniata

Includes Myxini (hagfish), Vertebrates

Myxini

have a partial cranium but no vertebrae. Their “skeleton” is made of cartilage
Marine animal that produce large quantities of slime as a defense
mechanism.
Virtually blind and rely on 4 tentacles to “sense” prey

Vertebrate

take their name from the dorsal vertebral column that replaces the notochord during early development as a primary supporting structure

Petromyzontida (Lampreys)

As adults, ________ are characterized by a rasping tongue within a
toothed, funnel-like sucking mouth. Many species have a parasitic
stage of their life cycle during which they attach to larger fish

Petromyzontida (Lampreys) are ________________ and the only _______

Vertebrate Chordates; jawless chordates

Gnathostomes

Jawed Vertebrates; Early gnathostomes are also characterized by two sets of paired fins, allowing the fishes to maneuver accurately

Pectoral fins are typically located on the __________, and pelvic fins on the _________

anterior body; posterior

Chondrichthyes

Are Cartilaginous Fishes; consists of sharks, rays and sawfishes.
These fishes have a skeleton composed entirely of firm but
pliable cartilage

Sharks

reproduce sexually, and eggs are fertilized internally. Most species
are ovoviviparous: the fertilized egg is retained inside of the mother.

The eggs hatch in the uterus, and young are born alive and fully functional

Chondrichthyes are ___________ and ___________

verterbrate chordates; jawed chordates

Osteichthye

Bony vertebrates are characterized by an internal skeleton of calcified rigid bone. Bony fishes are often covered by overlapping scales, and their gills are covered by a membrane

Many have a swim bladder

swim bladder

a gas-filled organ that helps to control the buoyancy of the fish

The vast majority of present-day fishes belong to this group, which
consists of approximately 30,000 species

Osteichthyes

Bony Fishes are further divided in 2 groups: ______________ and
______________

Ray finned fishes; Lobe finned fishes

Lobe finned fishes

have thick, supportive bones in the fins that allow
them to walk along the surface

Ray finned fishes

have thin, supportive bones in the fins

Tetrapods

4 limbs

Tetrapods split in two main groups: ________ and _________

Amphibians; Amniotes

Amphibians

loosely translates as “dual life,” which is a reference to the metamorphosis that many frogs and salamanders undergo and their mixture of aquatic and terrestrial environments in their life cycle

General Characteristics of amphibians

- Moist, permeable skin
- All amphibians need to live in or near water
- Many amphibians undergo complete metamorphosis
- A papilla amphibiorum and papilla basilaris, structures of the
inner ear that are sensitive to frequencies below and above 10,00
hertz

Amniotes

distinguished from amphibians by their terrestrially adapted egg, which is protected by amniotic membranes

dditional derived characteristics of amniotes

include waterproof skin, due to the presence of lipids, and costal (rib) ventilation of the lungs

amniote lineage split in 2 groups: _________ and ___________

reptiles; mammals

General Characteristics of reptiles

- Lay eggs enclosed in shells on land
-Reproduce sexually with internal fertilization
. - Scaly skin, containing the protein keratin and waxy lipids, which
reduced water loss from the skin
- Lungs
- Ectothermic

Squamates

Lizards and Snakes

Lizards

species range in size from chameleons and geckos to the Komodo
dragon. Most lizards are carnivorous, but some large species, such as iguanas, are herbivores

Snakes

are carnivorous and most snakes have a skull that is very flexible, involving eight rotational joints

Testudines

Turtles

Turtles arose approximately 200 million years ago. They are
characterized by a bony or cartilaginous shell. The shell consists of the ventral surface called the plastron and the dorsal surface called the carapace, which develops from the ribs

Theropods

Bird Ancestor

Theropod fossils and birds have similar hip and wrist bone structure

Birds

are endothermic. Feathers not only act as insulation but also
allow for flight, providing lift with secondary feathers and thrust with
primary feathers

Many bird bones are hollow rather than filled with tissue, containing
air spaces

4 key Features distinguish Mammals

1.Sweat glands

secrete sweats that evaporates

4 key Features distinguish Mammals

2.Mammary glands

in females secrete milk on which newborn feed

4 key Features distinguish Mammals

3.Hair

provides a protective and insulating covering

4 key Features distinguish Mammals

4.Unique heart

A four chambered heart

3 groups of Mammals living
today: _________, _________ and __________

Monotremes; Marsupials; Eutherians

Monotremes

unique among mammals as they lay eggs, rather than giving birth to young. Monotremes lactate but lack nipples; excreting milk from mammary glands via opening of the skin

Marsupials

Most species of marsupials possess a pouch in which the very
premature young reside after birth, receiving milk and continuing
to develop

Eutherians

sometimes called placental mammals, because all species possess a complex placenta that connects a fetus to the mother, allowing for gas, fluid, and nutrient exchange. Eutherians are the most widespread of the mammals, occurring throughout the world

Primates

Primates are characterized by:
1) a rotating shoulder joint
2) Opposable thumbs
3) Stereoscopic vision
4) Larger brains

Order Primates is divided into two groups: ________ and __________

Prosimians; Antrhopoids

Anthropoids

include monkeys, apes, and humans

great apes

include: the genera Pan (chimpanzees and bonobos) Gorilla (gorillas), Pongo (orangutans), and Homo (humans)