Chordate Comparison

What are the characteristics of a chordate?

• Dorsal hallow nerve cord• Notochord• Pharyngeal pouches• A tail beyond the anus

Subphylum Urochordata

• Tunicates• Filter feeders• Nerve cord• Notochord,pharyngeal pouches• Temporary tail• Gill slits

Subphylum cephalochordata

• Lancelets• Nerve cord• Notochord,pharyngeal pouches• Temporary tail• Gills• Closed circulatory system,no true heart• Muscle units

Fishes-jawless-lampreys’ class

• No true teeth or jaws• Fibers and cartilage in skeleton• Lack vertebrae and keep notochords• Filter feeders as larvae and parasitic as adults• Suck up tissues and body fluids

Fishes-jawless-hagfishes’ class• No true teeth or jaws• Fibers and cartilage in skeleton• Lack vertebrae and keep notochords• Feed on dead or dying fish with toothed

tongue• 6 hearts and open circulatory system

Class Chondrichdyes

• Sharks,rays,and skates• Cartilaginous skeleton• Toothlike scales on skin• May have 1000’s of teeth

Class Osteichthyes

• Bony fish

Organ systems in fish

• Fish may be herbivores,carnivores,parasites,filter feeders,detritus eaters

• Esophagus,stomach,pyloric ceca,liver,pancreas,anus

Organ systems in fish

• Most exchange gases using gills• Most have a single gill opening

• Lungfish can survive in O2 poor water

Organ systems in fish-movement

• Alternatly contacting paired sets of muscles on either side of backbone

• Creates s curve and tail propels forward• Swim bladder adjusts buoyancy

Organ systems in fish-reproduction

• Eggs fertilized externally or internally• Oviparous-eggs hatch outside body• Ovoviviporous-eggs hatch in mothers body-as

in guppies• Viviporous-embryos stay in mother’s body but

get nourishment from her,instead of from egg-example-sharks

Amphibians-anatomy and info• Lives in water as larvae and land as

adult• Moist skin w/glands and lacks scales

and claws

Amphibians-anatomy -digestion

• Tadpoles filter feeders and eat algae/adults meat eating

• Mouth,esophagus,stomach,small intestines(food absorption),large intestine,,cloaca(for urine ,wastes and eggs or sperm),liver,pancreas,gall bladder

Amphibians-anatomy -respiration

• Larvae-skin and gills/lungs in adults,usually/salamanders have poor lungs or none and respire through skin and mouth

Amphibians-anatomy -circulation

• Double loop-1st loop carries O2 poor blood from heart to lungs and skin /2nd loop carries O2 rich blood from heart to body and O2 poor blood back to heart

• 3 chamber heart

Amphibians-anatomy -excretion

• Kidneys to filter wastes from blood

Amphibians-anatomy -reproduction

• sexual• Eggs w/o shells• Laid in water• Larvae are tadpoles

Varieties

• Order urodela-salamanders and newts-long bodies and tails,usually 4 legs,in woods or water

• Order anura-frogs or toads• Order apoda caecillians-legless

Reptiles’ anatomy and info• Dry,scaly skin,lungs,eggs w/ several

membranes

Reptiles’ anatomy -Body temperature

• Ectotherms-external control/envi-ronmental control

Reptiles’ anatomy -feeding

• Herbivores and carnivores…and omnivores

Reptiles’ anatomy -respiration• Spongier lungs for more gas

exchange

Reptiles’ anatomy -circulation

• 3 chambered heart,except 4 in alligators and croc’s

• double

Reptiles’ anatomy -excretion• If water retiles excrete toxic

ammonia• If land reptiles excrete uric

acid

Reptiles’ anatomy- response,movement

• Many have sensory organs in roof of mouth

• Some have strong legs and some move in a s-curve

Reptiles’ anatomy -reproduction

• Internal fertilization• Lay eggs• Oviparous• Amniotic egg:4 membranes-

amnion,yolk,chorion,and allantois

Varieties of reptiles

• Order squamata-lizards and snakes• Order crocodiliains’s also alligators,caimans

and gavials• Order testudines-turtles(water) and

tortoises(land)-shell built into skeleton-2parts dorsal –carapace,ventral- plastron

• Order sphenodonta-tuataras-near New Zealand,resmble lizards but have 3rd eye

Birds-anatomy and info

• Reptilelike but have constant body temperatures -endotherms- with wings and feathers made of protein and developes from pits in bird skin

• Contour feathers and down• Flight is enabled by pneumatic bones w/ air

sacs

Birds-anatomy-feeding

• Must eat constantly,depending on size• Bills adapted to food getting• Have crop to store food• Gizzards to break down food physically• Esophagus,stomach,intestines,pancreas,liver,

cloaca

Birds-anatomy-respiration

• Most air 1st enters through air sacs in body cavity and bones,then the lungs through specialized tubes,flows in a single direction so always O2 rich-helps maintain high metabolic rate !!!

Birds-anatomy-circulation

• 4 chambered heart and 2 separate circulatory loops

• Complete separation of O2 rich and O2 poor blood

Birds-anatomy-excretion

• Uric acid fecal sacs-whitish

Birds-anatomy-Response

• better developed brain• Well developed eyes and optic lobe• Taste and smell usually not well developed

Birds-anatomy-movement

• Some do not fly,but most do• More rigid skeleton• Large chest muscles attached to large keel

Birds-anatomy-Reproduction

• Mating by cloacal positioning• Amniotic eggs but with harder shells

• Archaeopterx-transitional species leading to birds

• Passerines-largest order—perching birds• Piciforms arboreal

Mammals

• Have hair and mammary glands• Breathe air,4-chambered heart,endotherms

Nonplacentals

• Monotremes-egg-laying,have a cloaca• Platypus,spiny ant eaters• Marsupials-young develop in external pouch

Placentals

• Order insectivores--shrews,hedge hogs,moles• Order sirenians-manatees• Order chiropterns-bats• Order rodentia-mice,rats

squirrels,beavers,porcupines,gophers,chimp-munks…

• Order cetaceans-whales and dolphins

• Order perissdactyls--hoofed animals w/ odd # toes-horses,tapirs,rhinos,zebras

• Order carnivores-meat eaters--cats,dogs,foxes ,bears,racoons,walruses-some omnivores

• Artiodactyls-even- toed hoofed-grazing animals

• Xenathrans-no teeth-anteaters,armadillos• Primates

• Proboscideans—have trunks Asian and african elephant

• Lagomorphs-herbivores-hares and rabbits