>52,000 species; size ranges from 0.1 g to 100,000 kg; occupy nearly all habitats on Earth
basic characteristics of vertebrates
oviparous, ovoviviparous, viviparous
3 modes of vertebrate sexual reproduction
oviparous
condition of egg laying outside the body (internal or external fertilization)
ovoviviparous
modified live bearing without maternal connection; born encapsulated in membrane but nutrients from the yolk (not from placenta)
viviparous
live bearing with maternal connection; placenta delivers oxygen and nutrients
Animalia
Kingdom of vertebrates
Chordata
phylum of vertebrates
notochord, dorsal hollow nerve cord, post-anal tail, pharyngeal pouch/gill slits
4 distinct characteristic of chordate development
notochord
dorsal cartilaginous supportive rod
dorsal hollow nerve cord
usually enlarged at anterior end (brain)
postanal tail
not always present all of life; muscular structure at the end of a developing chordate
pharyngeal pouch/gill slits
most embryonic stages are in water; derivatives include thyroid and parathyroid
notochord is embryonic only; nerve cord and brain; tail is embryonic but small tailbone still extends; pharyngeal pouch in embryonic development and inner ear eustachian tuber derived from these
4 chordate characteristics in humans
tunicates: invertebrates, 3000 species, marine, filter feeders
subphylum urochordata characteristics
lancelets: invertebrates, 25 species, marine, filter feeders, oldest Phylum Chordata fossil in this taxon (~550 MYA)
subphylum cephalochordata characteristics
vertebrates
chordates with a backbone
chordate features; vertebral column; cranium; endoskeleton of cartilage or bone; Hox genes; neural crest
subphylum vertebrata characteristics
vertebral column
series of cartilaginous or bony elements
code for complex body forms
Hox genes and neural crest are important because they:
living endoskeleton, advancement of nervous system and cephalization, pharynx enlargement and jaw, paired appendages
four advances guiding vertebrate evolution
grows with the animal (not shed like exoskeleton)
advantage of living endoskeleton
brain size increases
advantage of advancement of nervous system and cephalization
larger mouth, larger food intake, larger organism
advantages of pharynx enlargement and jaws
better movement
advantage of paired appendages
pisces
refers to fish
tetrapoda
4 legs
gnathostoma
jawed mouth
agnathans (jawless fish)
cyclostomes
hagfishes: 70 species; lack jaws, eyes, fins, vertebrae; skeleton of notochord and cartilaginous skull; covered with slime
class mixini characteristics
lampreys: 25 species; lack jaws and appendages; covered with slime; oldest vertebrate fossils (510 MYA)
class cephalospidomorphi characteristics
class chondrichtheys and class osteichthyes and land vertebrates
gnathostomes
cartilaginous fishes: skates, sharks, rays; cartilaginous skeleton and notochord as adults; jawed; paired appendages; 1000 species; fossils 400 MYA
class chondrichthyes characteristics
bony fishes: most diverse vertebrate group with >26,000 species; most have bony skeleton; jawed; paired appendages; fossils 380 MYA
class osteichthyes characteristics
dipneusti, crossopterygii, actinopterygii
subclasses of class osteichthyes
fleshy-finned fishes: lungfishes; 10 species; South America, Africa, Australia
subclass dipneusti characteristics
lobe-finned fishes: coelocanth; 2 species; skeletal elements of limbs similar to Amphibians; ancestral stock to tetrapods
subclass crossopterygii characteristics
ray-finned fishes: > 26,000 species; rays = support for the fins; 3 distinct lineages distinguished by: form of tail, form of scales, structure of swim bladder
subclass actinopterygii characteristics
chondrostei, holostei, teleostei
superorders of subclass actinopterygii
surgeons and paddlefishes: 25 species; modern ones lack a complete bony skeleton; hardened cartilage vertebral column; notochord as adults; bones associated with skull; weak jaws; lack scales; heterocercal tail (notochord into upper lobe); swim bladder wi
superorder chondrostei characteristics
bowfin and gars: 8 species; Ganoid scales = thick, non-overlapping; slightly heterocercal tail (notochord to base of upper lobe); swim bladder with connection; teeth
superorder Holostei characteristics
>26,000 species; scales absent but if present = thin, lightweight, overlapping, mostly round; homocercal tail; swim bladder present (some with, some without connection); operculum; Webberian apparatus; Mauthnerian system
superorder teleostei characteristics
cycloid scales
thin, overlapping scales with a smooth posterior edge
ctenoid scales
thin flexible and overlapping scales in bony fish that have tiny spines
operculum
gill covering that aids in gas exchange
Webberian apparatus
chain of small bones between inner ear that conduct sound vibrations
Mauthnerian system
lower part of brain, two large nerve regions connected to acoustic nerve at base of brain and pick up sensory info from spinal cord and regulates "startle response
swim bladder
if the __ __ is absent, another buoyancy device is present
tetrapods
gnathostomes with 4 limbs
locomotion, reproduction, prevent desiccation, and gas exchange
the transition to land involved adaptations for:
sturdy lobe finned fishes
these evolved into animals with 4 limbs
vertebral column strengthened, hip and shoulder bones braced against vertebral column (pelvic and pectoral girdles), relatively simple changes in gene expression (especially Hox genes)
other characteristics that led to transition to land
hox genes 9-13 work together to specify limb formation from proximal to distal
how hox genes are related to limb development
9 = scapula (shoulder blade); 10 = humerus; 11 = radius, ulna, some carpals; 12 = carpals; 13 = metacarpals and phalanges
hox genes and what they specify
amphibios
living a double life
>4000 species; first tetrapod group; successfully invaded land but most reproduce in water; lungs; 3 chambered heart; external fertilization in water; very thin skin; mucous glands keep skin moist; poison glands for protection; most undergo metamorphosis;
class amphibia characteristics
lungs
in amphibians, an adaptation to a semi-terrestrial lifestyle
external fertilization
in amphibians, occurs in water where sperm and eggs are released to be fertilizaed
thin skin
in amphibians, thinnest of all vertebrates; no scales, feathers, or hair; some gas exchange
early tetrapod (360 MYA); had limbs and girdles; small scales and fin along top of the tail; ancestral group (most likely to be Crossopterygian fish); similarities to crossopterygians
ichthyostega characteristics
limb bones; digits; dentition; flattened skull; skull bones; 'neck-like' region
ichthyostega similarities to crossoopterygians
fishapod; broad skulls with eyes on top; lungs; pectoral fins with 5 finger-like bones; species increasingly lived on land but still tied to water for reproduction; 320 MYA, Cacops was similar to modern amphibians
Tiktaalik rosae characteristics
lissamphibia
modern amphibians; a subclass of class amphibia ; "smooth" "living a double life
anura, gymophiona, caudata
orders of subclass lissamphibia
frogs and toads; ~3500 species; ~90% of amphibians, ~60% of New World Tropics; carnivorous adults, herbivorous tadpoles; near worldwide distribution; saltatorial locomotion (jumping); front limbs < hind limbs; urostyle
order anura characteristics
urostyle
fusion of the caudal vertebrae into a rod-like structure to stabilize the back end of the body with the pelvis
caecilians; <200 species; nearly blind tropical burrowers (fossorial); secondarily legless; lack girdles; exhibit dermal folds that look like 'rings'; 'tentacle' out of eye socket functioning as sensory underground
order gymnophiona characteristics
salamanders; ~400 species; often have colorful skin patterns; most with 4 limbs; includes largest living amphibian (Andrias: giant Chinese salamander)
order caudata characteristics
amniotes
tetrapods with a desiccation resistant egg
shelled egg/amniotic egg
critical innovation of amniotes that broke tie to water
permeable to oxygen and carbon dioxide; 3 internal membranes; amnion, yolk sac, allantois, chorion;
characteristics of amniotic egg
birds = hard and calcareous; reptiles = soft and leathery; mammals = 3 egg layers (soft and leathery) or embryo embeds in uterine wall
different types of amniotic egg
amnion
protects embryo in the amniotic cavity
yolk sac
encloses a reserve of nutrients and gets smaller with age
allantois
contains wastes from embryo and gets bigger with age
chorion
together with allantois, allows gas exchange
amnion, allantois, chorion
the three internal membranes of the amniotic egg
desiccation resistant skin containing keratin; thoracic breathing; water conserving kidneys; internal fertilization
other key amniotic innovations
thoracic breathing
negative pressure sucks air in
water conserving kidneys
concentrate waste prior to elimination; "metanephric kidney
endothermic
'internal temperature'; body temperature is primarily controlled by trapped metabolic heat (birds and mammals)
ectothermic
'external temperature'; body temperature is primarily related to external temperature. metabolic heat is generated but difficult to capture/maintain the heat (fishes, amphibians, reptiles)
>8000 species; includes turtles, crocodilians, lizards, snakes, tuatara; live away from water; thicker skin and scales for protection; larger brain; larger limbs and muscles for better terrestrial locomotion; enhanced kidneys; amniotic egg; 3 skull lineag
class reptilia characteristics
anapsid
without arch" skull with no temporal openings
diapsid
2 arches" skull with 2 temporal openings
tuatara and crocodilians
have diapsid skull with openings one over the other
lizards and snakes
have diaposid skull with openings one next to the other
turtles and tortoises
have anapsid skull
fossil reptiles and birds
have diapsid skull with openings combined in '8 shape'
turtles and tortoises: anapsid skull; >400 species; fossils >200 MYA; carapace (top shell), plastron (bottom shell), epidermal scales, dermal scales; leatherback sea turtle is largest; 2 suborders
order testudinata characteristics
pleurodira (side necked turtles) and cryptodira (side necked turtles)
order testudinata suborders
alligators, crocodiles, caimens, gnarials: large size >7 m; fossils are relics of mesozoic era >20 m; diapsid skull; 4 chambered heart; thecodont dentition; enlarged cerebrum; elongate snout, teeth, body
order crocodylia characteristics
tuatara: 1 species; New Zealand and nearby islands; diapsid skull; fossils ~200 MYA; only male reptile lacking a copulatory organ
order rhyncocephalia characteristics
Sphenodon punctatus
only species in order rhyncocephalia
lizards, worm-lizards, snakes: >6000 species; diapsid skull; hemipenes; Jacobsen's organ; 3 suborders
order squamata characteristics
hemipenes
forked copulatory organ
Jacobsen's organ
auxillary olfactory organ at back of mouth cavity, chemical molecules picked up by tongue and analyzed
lacertilia, aphisbaenia, serpentes
suborders of order squamata
lizards: fossils ~240 MYA; ancestral group to two other lineages; oviparous, ovoviviparous, viviparous; size range 75 mm to 3 m; venomous (2 species of Heloderma, gila monster and beaded lizard); >3000 species; differences from snakes
suborder lacertilia characteristics
movable eyelids; nictitating membrane; external ear openings; jaws tightly fused in front and to the skull; dorsal and ventral scales same size; osteoderms; pelvic and pectoral girdles; most have 4 limbs; sternum; paired internal organs; reduction in numb
how lizards are different from snakes
osteoderms
bony plates under the scales that help support the scales
autotomy
easy breakage of a body part (such as the tail)
worm lizards: >200 species; tropical/subtropical distribution; fossorial (underground burrowers); reduced eyes; lack ear openings; autotomy; both girdles but reduced (most lack appendages)
suborder amphisbaenia characteristics
snakes: >2500 species; fossils ~250 MYA; fragile and lacking large bones; size range from 100 mm to 10 m; all carnivores; lack appendages; mostly lacking girdles (remnant in some); lack movable eyelids/nictitating membrane; brille; lack external ear openi
suborder serpentes characteristics
fang
elongate, hollow tooth; not present in all snakes
ahlyphous and glyphous dentition
different snake dentitions
aglyphous dentition
without long pipe" lack fangs
glyphous dentition
with long pipe" have fangs
opistoglyphous dentition
behind," rear-fanged, short (most nonvenomous)
proteroglyphous dentition
first," front-fanged, short/fixed
solenoglyphous dentition
long," front-fanged, long/moveable
birds: >10,000 species; evolved from small dinosaurs; fossils ~150 MYA; size ranges from 1.5 g/5.7 cm to 136 kg/ 2.4 m; adaptations for flight; oviparous
class aves characteristics
dominant approximately 215-65 MYA; 2 classes; legs positioned directly under the body; some may have been endothermic
dinosaur characteristics
ornithiscia and saurischia
dinosaur classes
class ornithiscia
bird hipped dinosaurs (Stegosaurus)
class saurischia
lizard hipped dinosaurs (t-rex)
may have enabled gliding, helped keep animal warm, or cut down glare when hunting
possible advantages of wings in transitional forms (between dinosaurs and birds)
avian features: feathered wings and tail
reptilian features: long bony tail, claws on wings, toothed beak, no large breastbone
Archaeopteryx lithographica characteristics
avian features: feathered wings and tail
reptilian features: short bony tail, claws on wings, toothed beak, no large breastbone
Caudipteryx zoni characteristics
avian features: completely feathers, no bony tail, no teeth in beak
reptilian features: flightless, claws on wings, no large breastbone
Confuciusornis sanctus characteristics
feathers, air sacs, reduction or organs, lightweight skeleton
features unique to birds for flight
feathers
modified scales that keep birds warm and enable flight (plumage); molted
air sacs
allow for efficient breathing in birds
reduction of organs
single ovary, no urinary bladder or teeth
lightweight skeleton
thin, hollow, honeycombed; furcula and synsacrum
furcula
'anterior protective box'; "wishbone" = sternum fused with clavicles; wing stability
synsacrum
'posterior protective box'; hindlimb stability; fusion of lumbar, caudal, sacral vertebrae into the pelvic girdle
hooked together and can be zipped together with beak
characteristic of keratin bird feathers
endothermic; warm body temperature; double circulation and 4 chambered heart; acute vision; most are carnivores; wide beak diversity; brooded eggs with lots of yolk; complex courtship rituals; diapsid skull; large orbits; 4 limbs; beak/bill; head with fle
other characteristics of birds
beak/bill
lacks teeth and heavy jaw bones; hardened keratinized sheath over jaws/nasal cavity
5th appendage
head with beak and long flexible neck sometimes called:
on chest and attached to furcula
location of flight muscles
pectoralis
pulls wing down; largest; ~15% of bird
supracoracoideus
lifts wing; ~10% of bird weight
glorified feathered reptiles
birds are sometimes called:
neornithes
subclass of class aves; 'new bird'
paleognatha and neognatha
superorders of subclass neornithes
'ancient jaw'; 5 orders; flightless, lack keeled sternum
superorder paleognatha characteristics
'new jaw'; 23 orders; keeled sternum; includes order passeriformes (largest group of >5000 species
superorder neognatha characteristics
order passeriformes
perching birds with perching feet; songbirds; robins, starlings, sparrows, warblers
order apodiformes
fast fliers with rapidly beating wings; small bodies; hummingbirds, swifts
order piciformes
large with specialized beaks, two toes pointing forward and two backwards; woodpeckers, toucans
order psittaciformes
large, powerful beaks; parrots cockatoos
order charadriiformes
shorebirds; gulls, sandpipers
order columbiformes
round bodies, short legs; doves, pigeons
order galliformes
often large birds, weak flyers, ground nesters; chickens, pheasants, quail
order accipitriformes
large diurnal carnivores, birds of prey, powerful talons, strong beaks; eagles, hawks, vultures
order coraciiformes
large beaks, cavirty nesters; hombills, kingfishers
order strigiformes
nocturnal carnivores, powerful talons, strong beaks; owls
order anseriformes
able to swim, webbed feet, broad bills; ducks, sawns, waterfowl
order pelecaniformes
large, water inhabiting; pelicans, frigate birds
order sphenisciformes
flightless, wings modified into flippers for swimming, marine, Southern Hemisphere; penguins
evolved from amniote ancestors earlier than birds; appeared ~225 MYA and evolved from small mammal-like reptiles; after dinosaur extinction, mammals flourished
class mammalia evolution
range of body sizes; body forms and complexity unmatched; 4 chambered heart; amniotic egg (oviparous and viviparous); 4 limbs with both girdles; enlarged braincase with increased cerebrum; synapsid skull; special dentition; mammary glands; hair with kerat
class mammalia characteristics
thecodont, heterodont, diphyodont
three mammalian dentition patterns
thecodont
condition of long rooted teeth embedded in sockets of the jaw bone
heterodont
condition of different types of teeth in the mouth (incisors, canines, premolars, molars)
diphyodont
condition of milk teeth being replaced by permanent teeth
corpus callosum
band of nerve fibers connecting the left and right sides of the cerebrum; larger allows faster transfer of nerve impulses
dentary
in mammals, jaw bone is one piece
pinna
a flap of cartilage and loose connective tissue to funnel sound waves into the outer ear
cenozoic era
last 65 million years; coincides with mass extinctions of Ruling Reptiles
therapsids
probably ancestral reptile groups
synapsid skull, middle ear ossicle(s), limbs under body, bipedal, thecodont, increased brain, 'separation' between thoracid and abdominal cavities
therapsids characteristics
prototheria and theria
subclasses of class mammalia
first" "wild beast"; order monotremata, 'one opening'; 3 living species: duckbilled platypus, spiny anteater, echidna; oviparous = leathery shell; fossils ~200 MYA, probably several groups at one time; cloaca; incubate eggs; no nipples; Australian region
subclass prototheria characteristics
cloaca
chamber receiving the contents of the urinary, reproductive, and digestive tracts
wild beast"; diverged into two distinct groups at 160 MYA
subclass theria characteristics
metatheria and eutheria
infraclasses of subclass theria
marsupials: 7 orders, 250 species; viviparous = weakly developed placenta, cannot maintain placental connection long-term, offspring are born in underdeveloped state; marsupium; motor/sensory coordination skills poor; smaller brain and poor corpus callosu
infraclass metatheria characteristics
placental mammals: "true wild beast"; >6000 species; 18 orders; placenta; increased brain case with cerebrum and corpus callosum; teeth specialization; earliest placental mammal group = proeutherians (small insectivores)
infraclass eutheria characteristics
plant eating; gnawing habit with two pairs of continually growing incisor teeth; >2200 species; more individual rodents than all other mammals together; high reproductive rate, short gestation; lack canines and have gap = diastema; mice, rats, squirrels,
order rodentia characteristics
insect or fruit eating; small; flight = only flying mammal; navigate by sonar; nocturnal; >900 species; keeled sternum with increased pectoral muscles; lightweight skeleton; elongate forelimb and phalanges bones = stretched out to expand the chiropatagium
order chiroptera characteristics
insect eaters; primitive placental mammals; shrews, moles, badgers
order eulipotyphyla characteristics
chiropatagium
flight membrane apparatus; 'wings' of bats
primarily tree dwelling species; evolved ~85 MYA; grasping hands with opposable thumbs; large brain; some digits with flat nails; binocular vision; complex social behavior and well-developed parental care; flattened face; reduced nasal cavity; tactile sen
order primates characteristics
strepsirrhini and haplorrhini
two primate groups
wet noses, no fur at tip; generally nocturnal and smaller-brained; bush babies, lemurs, pottos
strepsirrhini characteristics
dry, furry nose, forward-facing eyes; tarsiers; anthropoidea
haplorrhini characteristics
large-brained and diurnal; monkeys; hominoidea
anthropoidea characteristics
gibbons, gorillas, orangutans, chimpanzees, and humans
hominoidea characteristics
flesh-eating mammals; enhanced canines with sharp points; increased vision (large eyes); increased nasal cavity and sense of smell; increased hearing; cats, dogs, weasels, bears, seals, sea lions
order carnivora characteristics
herbivorous hoofed mammals; usually two toes; some have four toes; many with horns or antlers; utilized by humans as domestic forms; deer, antelopes, cattle, sheep, goats, camels, pigs
order artiodactyla characteristics
pouched mammals; mainly found in Australia; kangaroos, koalas, opossums, wombats
order diprodontia charcteristics
powerful hind legs; rodent-like teeth; rabbits, hares
order lagomorpha characteristics
marine fishes or plankton feeders; front limbs modified into flippers; no hind limbs; little hair except on snout; whales, dolphins
order cetacea characteristics
hoofed herbivorous mammals with odd number of toes; one or three; some utilized by humans as domestic forms; horses, zebras, tapirs, rhinoceroses
order perissodactyla characteristics
egg laying mammals found only in Australia and New Guinea; duck-billed platypuses, echidna
order monotremata characteristics
long trunk; large upper incisors modified as tusks; elephants
order proboscidea characteristics