DOMAIN- Eukarya
KINGDOM- Animalia
PHYLUM- Chordata
•SUBPHYLUM- Vertebrata
 CLASS- 7 different
 ORDERS- 10 Placental mammals

Recall that vertebrates are chordates.
Phylum Chordata includes the lancelets and tunicates (invertebrate chordates) as well as the vertebrates
All chordates have:

• flexible rod-like structure
• main longitudinal structural element of chordates and of the early embryo of vertebrates
• plays an organizational role in nervous system development
• becomes part of the vertebral column .

Gill-like slits on vertebrates in embryo stage
Disappear in most adults
Continue on in some vertebrates

Characteristics of all Vertebrates
Endoskeleton with a backbone for support of a dorsal nerve cord & muscle attachment
Distinct skull/cephalization (head)
Bilateral symmetry (like us!)
2 pairs of jointed appendages
Coelom (cavity within between middle and inner tissue layer)
Closed circulatory system & chambered heart

Major Groups of Vertebrates
•Fish – aquatic tetrapods with scales, gills, & 2 chambered hearts
•Agnathans – jawless fishes – hagfish and lampreys
•Chondrichthyes – cartilagenous fish - sharks & rays
•Osteichthyes – bony fish – mahi-mahi, tilapia, halibut, puffer fish, tetras, guppies
•Amphibians – semiaquatic tetrapods with split lives & 3-chambered hearts
•Anura – “tailless ones” – frogs & toads
•Urodela – “tailed ones” – salamanders & newts
•Apoda – “legless ones” - caecilians
•Reptiles – terrestrial amniote tetrapods with scales & lungs & 3-ish to 4 chambered hearts
•Squamata – lizards and snakes
•Testudines – turtles & tortoises
•Crocodilia – alligators, crocodiles, and related species

•Birds – terrestrial amniote tetrapods with feathers & lungs & 4 chambered hearts
•Ratites – ostriches, emus, kiwis
•Passeriformes – perching birds – jays, sparrows, crows, etc.
•Aquatic birds – ducks, swans, geese
•Raptors – eagles, falcolns, hawks
•Penguins
•Mammals – terrestrial amniote tetrapods with lungs, hair and mammary glands & 4 chambered hearts
•Monotremes – echidna and platypus
•Marsupials – koala, kangaroo, opossom
•Placentals – humans, bears, tigers, giraffes, deer, pigs, dogs, cats, raccoons, squirrels, whales, walruses, manatees, etc

•Gill – respiratory structure that uses countercurrent exchange to extract oxygen from water
•Operculum – gill covering in bony fish
•Lateral line - a row of microscopic organs sensitive to pressure changes, can detect low frequency vibrations.
•Swim bladder – internal, air-filled sac that acts as an organ for buoyancy in bony fish; sharks have oils in their livers to help them remain buoyant
•Scale – small, platelike structure covering an organism (or parts of an organism); sharks, fish, reptiles, and birds all have different types of scales
•Fin – paired appendage found on fish used for locomotion and steering
•Reproduction
•External fertilization – release of gametes to the environment where fertilization takes place; bony fish
•Internal fertilization – deposition of sperm in the female reproductive tract where fertilization takes place; sharks
•Hermaphrodite – some organisms are capable of producing both male and female gametes; few are capable of self-fertilization; most exchange sperm; evolutionary adaptation for solitary and slow-moving or sessile organisms
•Ovoviviparous = eggs are fertilized inside the parent and hatch inside the parent and are born live
Oviparous = eggs are laid in a nest or in the ground and hatch
Viviparous = internal fertilization with live born young (as soon as the egg is fertilized, it becomes an embryo and develops as a fetus).

Hagfish – a detritivore
Hagfish and lampreys
Jawless & finless
Skeleton of cartilage
Reproduce sexually
Gills
2 Chambered Heart
Oviparous
Lamprey – an ectoparasite

Gills are supported by cartilage or bone. Some of these gill supports became other structures, including the jaws and inner ear bones of other vertebrates.

Class Chondrichthyes – sharks and rays
Endoskeleton made of cartilage
Paired fins
Jaws
2 chambered heart
Well-developed sense of sight and smell
Lateral line system (for sensing pressure changes – vibrations - in water); whole body acts as an “ear”
unique scales; teeth may be modified scales
Oviparous, ovoviviparous, and a few are viviparous
Internal fertilization using claspers to deposit sperm in female reproductive tract

Sharks have a unique digestive structure called spiral valve that increases surface area
Can detect electrical fields of living organisms with special pores in their skin (not the same as the lateral line system which they also have)
Sharks & some rays are carnivores
Rays (and the largest sharks) are suspension feeders

Tuna, perch, bass, clown fish, eels, seahorses, goldfish, catfish, etc….
* One of the most successful groups on Earth – ever!
Endoskeleton made of bones
Swim bladder
Usually, external fertilization & oviparous (think caviar)
Lateral line system
Scales different from those in sharks
2 chambered heart (all fish!)
Water balance important; some fish excrete salt through their gills, others very watery nitrogenous waste using kidneys

Three main groups of Osteichthyes – bony fish
Above: internal anatomy of a ray-finned fish left - photo of a lobe-finned fish; right – photo of a lungfish

FEEDING – herbivores, carnivores, filter feeders, etc.
RESPIRATION – Most have gills that absorb oxygen by diffusion from water to blood. A few also have lungs.
CIRCULATION – two-chambered heart that pumps blood in loop around body.

EXCRETION – Kidneys expel waste as ammonia. Salt water fish must retain water that leaks out of them, so they have very concentrated urine. Fresh water fish have water leak into them, so must constantly expel very d________ urine.
Solid waste is expelled from stomach.

SENSES AND RESPONSE – brain at end of spine. Very good senses of sight smell pressure/movement (lateral line) hearing less good
Pain? Evidence is inconclusive…

MOVEMENT– muscles move fins
Scales reduce resistance swim bladder filled with air/gas to adjust buoyancy
REPRODUCTION – most have external fertilization. Eggs hatch outside body
(oviparous)
Some fertilize eggs in body and keep eggs until hatched inside (ovoviviparous)
Sharks etc. viviparous embryo gets nourishment from mother.

Aquatic tetrapods gave rise to the first amphibians, who probably came on land in search of food
(abundant plant and arthropod species in Devonian)

Amphibian Vocabulary
Ectotherm – organism that must gain (or lose) heat from the environment to maintain body temperature; metabolism is NOT sufficient to heat the body; most invertebrates, fish, amphibians, & reptiles
Endotherm – organism that maintains a stable body temperature through metabolism; few reptiles, most birds and mammals, insects
Metamorphosis – change from a sexually immature stage to a sexually mature stage in the life cycle; involves change in body structure and niche; ex) tadpoles are herbivorous, aquatic larvae with gills and no limbs that change into carnivorous, terrestrial adult frogs with lungs and 4 limbs
Tetrapod – vertebrate with 4 limbs located in pectoral and pelvic girdles
Lungs – internal respiratory organs that exchange gases across a membrane surface, usually in conjunction with the circulatory system
Cloaca – common opening to the outside of the body through which fecal material, nitrogenous waste and gametes pass; common to amphibians, reptiles, and birds

live in water and on land, breathe with lungs and through skin, moist skin, no scales

Frogs, toads, salamanders, and newts
Ectotherms
Need H
2
O for breeding
Metamorphosis (tadpole  frog)
Gas exchange through moist skin & mouth; primitive balloon-like lungs
Goos eyes, tympanic membrane
External fertilization
Oviparous
3-chambered heart
Many have chromatophores in the skin for coloration, as well as poison glands for defense
Nitrogenous waste varies – aquatic habitat – dilute urine; terrestrial, concentrated urine

3 major groups of amphibians:
Apoda – caecilians; legless
Anura – frogs & toads; tailless
Urodela – salamanders & newts

FEEDING – tadpoles filter feeders/herbivores. Adults carnivores.
Many have long sticky tongues
RESPIRATION – tadpoles through skin and gills, adults have lungs and breathe through skin
CIRCULATION – three-chambered heart that pumps blood in double loop around body.

EXCRETION – Kidneys expel waste through cloaca. Solid waste is expelled from stomach.
SENSES AND RESPONSE – brain at end of spine. Very good senses of sight (big eyes, covered with nictitating membrane to protect eye.) hearing (tympanic membrane behind eye acts as ear)

MOVEMENT– tadpoles swim like fish
Frogs strong hind legs to jump.
Salamanders walk or run.
REPRODUCTION – external fertilization.
Eggs hatch outside body (oviparous) in water.


Terrestrial

Well-developed lungs

Dry scales and waterproof skin, amniotic eggs with shells allow for living on land without drying out

Control body temperature by moving into/out of sunlight

Reptile Vocabulary
Amniotic egg – adaptation to terrestrial life that results in a water-proof egg with extra-embryonic membranes that aid in the vital functions of a living organism
Extinct – all members of a species have died; ex) pterosaurs
Extant – members of a species are still alive
Bask – behavioral adaptation of ectotherms to increase body heat; involves moving to locations where more radiant energy (such as from the sun or warm rocks) is available for absorption

Amniotic egg in reptiles
- note leathery shell characteristic of reptilian eggs

turtles, snakes & lizards, crocodiles
Ectotherms – bask and hide to regulate temperature*
Scaly, waterproof skin
Respire through lungs only**
Internal fertilization
Oviparous, ovoviviparous, viviparous (depending on species)
3 or 4 chambered heart
Nitrogenous waste is a paste rather than a liquid for water conservation; uric acid
Extinct reptiles include dinosaurs and pterosaurs, which dominated the Earth during the Triassic period

Major extant groups of reptiles:
Squamata – snakes & lizards
• both snakes and lizards shed their skin as they grow
•Loss of legs is unique to snakes within the reptiles; remnants of pelvic girdles present in boas, as are external claws on the abdomen
• many have unique adaptations for life as predators
•Jacobson’s organ – when a snake flicks its tongue it is collecting molecules that are then brought in to Jacobson’s organ for “processing”; kind of a combined sense of taste and smell
•Pits – many snakes have heat sensory organs on their head that gives an IR picture of an organism, decreasing dependency on vision
•Hollow fangs – with or without poison glands for capturing, holding, and killing prey
•Muscles the length of the body allow it to move quickly and many use those muscles for immobilizing and strangling prey

Major extant groups of reptiles: (cont’d)
Testudines – turtles and tortoises
* Some are herbivorous, but most are carnivorous
•Lay eggs on land (oviparous)
•Cloaca is secondary respiratory surface in aquatic species **
•Shell is part of the body, connected to muscle and intimately intertwined with the skeleton

Major extant groups of reptiles: (cont’d) gharial crocodiles
Crocodilia – alligators and crocodiles
(caiman, and other related species)
•Adapted for aquatic life with upturned nostrils and eyes on top of head
• endothermic*
•4-chambered heart
•Related to feathered reptiles
American alligator

FEEDING – Some lizards and turtles are herbivores; snakes and crocodiles are carnivores http://www.youtube.com/watch?v=p-nj_iOBDqA
RESPIRATION – well-developed lungs
CIRCULATION – double loop blood flow to heart with two atria and one or two ventricles

EXCRETION – Kidneys expel waste as ammonia through cloaca. Solid waste is expelled from stomach.
SENSES AND RESPONSE – brain at end of spine. Very good senses of sight smell taste – tongue and organ in mouth sense vibrations with skull body heat – rattle snakes

MOVEMENT– Strong legs and body muscles allow rapid movement
REPRODUCTION – eggs laid on land after internal fertilization; leathery, waterproof shell
Males have penises (snakes have two) that penetrate female body.

Bird Vocabulary
Feather – modified scale used for flight and insulation (contour and down)
Keel – sternum modified for flight muscle attachment
Ratite – flightless birds
Beak – adaptation to the diet of a bird; cranial structure used for feeding and defense
Air sac – pocket attached to the lungs that aid the bird in maintaining constant air flow into the lungs, allowing for flight at high altitudes and greater muscle use
Preen gland - gland located on the base of the tail, especially in aquatic birds, that produces oil for waterproofing the feathers
Crop – portion of esophagus used for temporary storage of food
Gizzard – chamber of the stomach for grinding food

Birds
Endothermic
4 chambered heart
Internal fertilization
Oviparous
Amniotic eggs with calcerous, hard shells
Cloaca
Nitrogenous waste paste-like for water conservation; uric acid
Beaks and claws modified for specific niche
Classified as reptiles by many taxonomists
Digestive system modified for diet, including crop & gizzard

Many modifications for flight:
-Only organism with feathers (modified scales) for flight and insulation
-Evolutionarily may have began as courtship or defensive displays (behavioral adaptation, rather than for flight)
-Hollow bones - make bird lightweight
-Front limbs modified into wings
-Air sacs to aid in breathing at high altitudes
-Unique muscle tissue for sustained, intense use
-Keel – modified breastbone for muscle attachment
Birds migrate – move long distances on a seasonal cycle to reach mating and/or feeding grounds

8600 species of birds in 28 orders
•Flightless birds called ratites – emu, ostrich, kiwi
•Penguins have wings modified for swimming
•Aquatic birds have preen gland to keep their feathers from becoming saturated, impeding flight
•Most birds are passeriformes – perching birds, including jays, swallows, sparrows, and warblers (see pp. 790 & 91 in your text for more groups of birds)
Bird courtship and mating behaviors are an evolutionary adaptation unique to each species
Many other groups of birds, including birds of prey, marine birds, seed eaters, woodpeckers, hummingbirds, etc

FEEDING
- birds generate own body heat
- need large amounts of food
- beaks adapted for specialized feeding
- no teeth
- food stored in crop, then moves to one/two part stomach (gizzard) for grinding up (by stones!) and to intestines

RESPIRATION – well-developed lungs and air sacs to ensure one-way flow of air through lungs. Why important?
http://www.youtube.com/watch?v=iigxJXFJF4U

CIRCULATION – double loop blood flow through heart and lungs and body, like humans

EXCRETION – Kidneys expel waste as uric acid through cloaca. Semi-solid waste (white) is expelled from stomach.

SENSES AND RESPONSE
well-developed brain
- very good colour eyesight
- good hearing
- taste, smell not too good
- migrate using sun, magnetic field, visual markers, smell combination

MOVEMENT
- hollow bones with strengthening struts make birds light for flying
- strong chest muscles attached to sternum enable flight
- feathers provide aerodynamic shape

REPRODUCTION
- Mating is seasonal
- male bird usually mounts female to allow cloacas to touch and transfer sperm; some male birds have a penis
- fertilized eggs are enveloped with shell and laid through cloaca
- incubation can take from 11-90 days
- chick breaks open shell with an egg tooth

Egg hatching http://www.youtube.com/watch?v=0Z87u9t6Nww
Bird migration http://www.birds.cornell.edu/allaboutbirds/studying/migration/ http://www.youtube.com/watch?v=bte7MCSBZvo Arctic Terns

Mammal Vocabulary
Mammary gland – gland adapted to produce protein and fat rich nutrition for offspring during early development
Hair – keratinous growth for insulation, camouflage, and display; made of same material as reptilian scales and bird feathers
Fat – layer of connective tissue for insulation and padding; energy reserve
Diaphragm – sheet of muscle separating thoracic and abdominal cavities used in respiration
Monotreme – mammal that lays eggs
Marsupial – mammal with young that finish developing in a pouch
Marsupium – pouch in a marsupial
Placental – mammal whose young develop in a uterus attached to a placenta
Uterus – muscular organ that houses the fetus until birth
Placenta – extraembryonic tissues that develop as a connection between the circulatory system of the mother and that of the developing fetus
Dentition – tooth pattern; varies with diet; ex) reptilian dentition is characteristically uniform conical teeth for capturing prey, mammalian dentition varies significantly (carnivores, herbivores, insectivores, baleen, omnivores)

Humans, bears, pigs, horses, dogs, cats, whales, elephants, mice, koalas, platypus
Endothermic – hair and layer of fat aid in conserving heat
Hair – keratinous protein that aids in insulation
Mammary glands – produce milk to feed offspring
Internal fertilization
- 2 species of monotreme; oviparous
- Marsupials and placentals are viviparous
Diaphragm for increased respiration & spongy lungs for increased surface area
4-chambered heart
Dentition & jaw structure reflect diet
Inner ear contains 3 bones for improved hearing
Large brain; learn; Extended parental care
Most effective kidney for water conservation; urea

Evolutionary advances in jaw structure, dentition, and inner ear structure from reptile to mammal

3 categories of mammals
1. Monotremes
- mammals that lay eggs, have hair, and produce milk with mammary glands
mother produces milk which is excreted from glands on the abdomen and the babies lap up the milk or suck it off the fur of the mother
Echidna and platypus
Platypus has a cartilaginous bill used to find food on the bottom of a pond or river.
Males have poisonous spurs on their hind feet for defense
Platypi store fat in their beaver-like tails

2. Marsupials
embryo develops in a uterus with a placenta
Immature fetus is born into a pouch called a marsupium.
Young develop in marsupium, attached to a teat, until much more mature.
All marsupials live in Australia with the exception of the opossum, which can be found in the
Americas.

Interesting Evolutionary Note
Marsupials and placentals show parallel evolution

3. Placentals
Placental mammals develop in a uterus attached to a placenta until at a comparably advanced stage of development
Widespread on earth – found in every major biome, including marine, arctic, and tundra.
Many orders of placental mammals. 10 discussed as follows:

Rodentia- razor sharp teeth (rats, squirrels)
Lagomorpha- fused hind leg bones (rabbits)
Chiroptera- flying mammals (bats)
Carnivora- eat meat (lions, tigers, wolves)
Cetacea- Blow holes to breathe (dolphins, whales)
Insectivora- eat insects (moles, shrews, hedgehog)
Artiodactyla- even # of toes (cows, sheep, goat, pigs, hippos, camels)
Perissodactyla- odd # of toes (horse, zebra, rhino)
Proboscidea- trunks (elephants)
Primates- opposable thumbs (apes, monkeys, humans)

Order Primates
Prosimians – lorises, lemurs, tarsiers
Monkeys – New World Old World
Prehensile tails

Apes Humans
Gibbon
Gorilla
Orangutan
Chimpanzee

FEEDING
- Eat 10X what reptiles eat (Why?)
- carnivores, herbivore, omnivores
- adapted jaws and teeth

RESPIRATION
Lungs are filled by muscles (diaphragm and intercostal musles) expanding the chest cavity.

CIRCULATION
Blood circulated through body and lungs by a four-chambered heart and many blood vessels.

EXCRETION
Mammal kidneys filter out urea and other waste products.
Kidneys ensure water and salt levels in body stay constant.

SENSES AND RESPONSE
Mammals have well-developed brains, controlling many parts of their bodies and actions.
Senses include …. And are often better in other species than in humans.
Can dogs see colour? Can we hear what dogs hear?
http://www.youtube.com/watch?v=gZxLUNHEmPw http://www.youtube.com/watch?v=gZxLUNHEmPw

MOVEMENT
Muscles and skeleton enable complex and rapid movement.
http://www.youtube.com/watch?v=0K4XKTx7T4g

REPRODUCTION
Males deposit sperm internally into females.
Young develop in their mother’s uterus and are fed, given oxygen and have wastes removed through the placenta in the uterus.
Live-born young drink milk from the mother’s breasts.
Care of young can be communal and take many years.

See earlier slides for a brief description.