• blastopore develops into anus and mouth forms later in embryonic development

• exhibit radial symmetry(seastars)or bilateral symmetry(mammals)
• are triploblastic coelomates
• all experience radial cleavage
• all contain an internal skeleton

1) Echinoderms

2) Hemichordate

3) Chordates

Have a bilaterally symmetric larval form but exhibit radial symmetry as adults. Known as Pentaradial symmetry.

Have no head region

  Oral side:side containing the mouth

  Aboral side: side containing the anus

calcified plates that fuse together

Have a unique vascular system

     Locomotion

     Gas exchange

     Feeding

The classes of echinoderms

 Crinoidea

     feather stars, sea lilies

 Echinoidea

     sea urchins, sand dollars

 Holothuroidea

     sea cucumbers

 Ophiuroidea

     brittle stars

Acorn worms and pterobranches have a worm-like body organized in 3 parts: Proboscis, collar, and trunk.

live in burrows

pharyngeal gill slits

muscular pharynx

pharyngeal gill slits

post anal tail

notochord

dorsal hollow nerve cord

Cephalochordates

Urochordates

Verebrates

Lancelets: Occur in marine and brackish sediments

       filter feeders

sessile (but swim occasionally)

such as Amphioxus

Urochordates

Ascidians:Tunicates (sea squirts)

occur in marine environment

  sessile adults are filter feeders

         free swimming larvae (tadpole like)

 in early development.

        evolved in marine environment

Now are marine, freshwater, terrestrial, and even aerial

Jawless fishes: have circular mouths wih rasping tongues

1) Agnathan (Jawless fish)

produce slime as a defense mechanism

weak circulatory system (closed)

no jaws

no stomach

can change sex from year to year

Agnathan

no jaw

rudimentary vertebrate (has cartilage)

mostly parasitic

mostly freshwater

has 7 gill slits

vertebrates that have jaws

     evolution of jaws improved feeding efficiency

jaws and teeth make it easier to capture, subdue and swallow prey

Acanthodians and placoderms are the earliest jawed fishes but are now extinct

sharks,skates,rays,ratfishes,and chimeras

1)cartilaginous skeleton

2)sharks maintain buyancy by storing oils in their liver

3)streamlined bodies with paired fins

Ampulla of Lorenzini: electrochemical receptors concentrated around the head and along the sides of the body (lateral line)

Bony fishes: have an ossitied endoskeleton

1)operculum:a protective bony flap that covers and protects the gills

2)swim bladder:an air sac used to maintain buoyancy

3)Lateral line:row of tiny pits on either side of the body that senses movement in the water

1)Actinopterygii

2)Sarcopterygii

first class that superclass Osteichthyes (boned fishes) are classified into

ray finned fishes

~30,000 species

originated in freshwater the colonial marine habitats

some anadromous species

Exploit almost any imaginable food source

2nd classification of Superclass Osteichthyes (boned fishes)

Lobe finned fishes

Coelacanth

   living fossil

lungfish

   tetrapod ancestors

Gnathostomes that have limbs and feet

modifications of a pre-existing body plan

   limbs evolved form pectoral and pelvic fins

Pharyngeal gill slits evolved into ear bones

ears adapted to detect airborn sounds

Class Amphibia

(Tetrapod)

frogs, salamanders, and caecilians

closely tied to aquatic environments

     aqauatic larval form(tadpole) even if adults live in    terestrial habitats

Some secrete poisonous mucous

many rely on their moist skin for gas exchange

Amnitoes

(Tetrapod, class amphibia)

named for the major derived character of the clade: the amniotic egg

-adaption for terrestrial life

Most amniotes have less permeable skin to reduce water loss, and an elevated stance for easier locomotion

Amniotic Egg

(Tetrapod, class anphibia)

Calcareous shell protects against desiccation membranes

allantois:disposal sack for metabolic wastes produced

by the embryo

      1)amnion:protects the ecbryo in a fluid filled cavity

2)chorion:membrane involved in gas exchange

   3)yolk sack:contain a stockpile of nutrients to be used by the developing embryo

Class Reptilia

(Tetrapod)

 include lizards, snakes, crocodilians, tuatara, turtles, and birds (avian reptiles)

scales create a waterproof barrier that helps prevent dehydration

 -also prevents breathing through skin so most reptiles rely on lungs

 -mostly ectothermic(except birds are endothermic)

 -adapted to life in many different environments

Anapsids

(Reptile, class reptilia, tetrapod)

turtles and tortoises

   -skulls have no openings by the temples

 All turtles and tortoises have a boxlike shell that is fused to the vertibrate, ribs, and clavical.

   -side necked

   -vertical necked

Live in desterts, marine environments or ponds and rivers

   -most are omnivores that eat a variety of aquatic plants and animals

Diapsids

(reptiles, class reptilia, tetrapod)

have a pair of holes on each side of the skull, behind the eye scoket

2 main lineages

   1) Lepidosaurs:tuatara, lizards, and snakes

   2) Archosaurs:Crocodilians, dinosaurs, and pterosaurs

Lepidosaurs

(reptile,class reptilia,tetrapod)

Tuatara:living fossil found on islands off the coast of New Zeland

1)Lizards:most divers group of retile alive today (except birds);most are small bodied but some are large carnivores (Kimodo Dragon)

2)Snakes:Legless carnivores, some have chemical receptors or heat detecting organs to find prey

Archosaurs

(reptiles, class reptilia, tetrapod)

1) Crocodilians:the only living archosaurs

     -alligators and crocodiles

2)Dinosaurs:most were ectothermic but some were endothermic

     -mass extinction 65 m.y.a.

3)Pterosaurs:first tetrapods to fly, but their wings were completely different from birds and bats

Birds

("class" Aves, tetrapod)

Have many adaptions for flight

     -feathers

     -wings

     -reduced gonads

     -hollow bones

     -flow through lungs (one way)

feathers evolved before powered flight

     -for courtship

     -for camouflage

     -for insulation

Mammals

(class mammilia, tetrapod)

synapsids:mammals and mammal like reptiles have 1 hole behind their ear

underwent an adaptive radiation after the mass extinction of the dinosaurs

what are the 5 characteristics of mammals

(class mammalia, tetrapod)

1)Mammary glands:produce milk for offsprings

2)Hair:for protection and insulation

3)4 chambered heart:completely seperates oxygenated and deoxigenated blood

4)Sweat Glands:used for evaporative cooling

5)Differentiated teeth

Subclass prototheria

(mammals, class mammalia, tetrapod)

Monotremes:lack nipples but still produce milk that their young lap up off the mother's stomach hair

     -Platypus and echidnas

     -Native to Australia and New Zeland

Subclass Theria, infraclass metatheria

(mammal, class mammalia, tetrapod)

  Marsupials:Born very early in development, then completely develop in maternal pouch

     -nipples provide milk for the young

          (e.g. opossums, kangaroos, koalas)

Subclass Theria, Infraclass Eutheria

(mammal, class mammalia, tetrapod)

Placental mammals:Embryonic development occurs inside the uterous, connected to the mother by a placenta

     -fill a wide variety of ecological niches left open when the dinosaurs died off

Order Primates

(mammal, class mammalia, tetrapod)

Eutherian Primates radiated from a small, insectivorous mammal

Major adaptions

     -grasping limbs

     -opposable digits

     -binocular vision

2 main clades

     -prosimians

     -anthropoids

Family Hominidae

(mammal, class mammalia, tetrapod)

bipedal locomotion

     -elevates the head

     -less energy than quadrupedal locomotion

     -allows forelimbs to carry other objects while walking

Early Hominids

(mammals, class mammalia, tetrapod)

Human ancestors originated if Africa

Australopithecus (i.e. Lucy)

     -first hominid discovered

     -lived in Africa ~4-5 m.y.a.

Homo habilus

     -used tools to obtain food

Homo Erectus

     -first hominid to leave Africa (went to Asia)

     -used fire for cooking and hunting

Homo Sapiens

(mammals, class mammalia, tetrapod)

Brain size increased as hominids evolved

     -extra brain capacity allowed for the evolution of complex language & culture

Allowed for the domestication of plants & animals

Agriculture allowed for an increasingly sedentary lifestyle

     -formation of cities

     -occupational specialization