Vertebrates II Bio 1108

Amniote

Member of a clade of tetrapod vertebrates that include reptiles (including birds) and mammals

Amnion

a protective membrane that encloses the embryo in a fluid-filled cavity

Advantages of an amnion egg

Allows the embryo to develop on land without desiccating and providing a greater degree of protection and facilitating the successful colonization of terrestrial environments

reptiles, birds, and mammals

Traditional classification of 3 living amniotes

Innovations of Amniotes

• desiccation resistant skin

• thoracic breathing (negative pressure sucks air in)

• Water-conserving kidneys- concentrate waste prior to elimination

• internal fertilization

Amphibians

Which class did amniotes develop from?

Synapsids and Sauropsids

Two major group of amniotes

Synapsids

Mammals with one temporal fenestrae

anapsids and diapsids

Two groups that make up sauropsids

Anapsids

no temporal fenestrae; turtles

diapsids

two temporal fenestra; birds and reptiles

temporal fenestra

openings in the skull, behind the eye sockets, that are important for the attachment of jaw-closing muscles

300 mya; Carboniferous period

When did reptiles emerge and during which period?

Archosaurs

This group of reptiles includes dinosaurs, crocodile, alligators, bird

Lepidosaurs

This group of reptiles includes lizards, snakes, and tuataras

ecotherm

body heat is dependent on the environment

crocodilia

this order contains crocodiles and alligators

Sphenodontia

This order contains tuataras; two species live in New Zealand

Squamata

This order contains lizards and snakes; largest group of reptiles; found everywhere but Antarctica; diverse

Testudines

This order contains turtles; ventral shell surface called plastron; dorsal shell surface called carapace, forms from ribs

Birds

These animals are:

• endothermic

• have a high metabolic rate as flight s metabolically expensive

• have modifications for flight

  • Feathers are modified scales

    • Aid in insulation

  • Hollow bones

  • Sternum in the shape of keel

    • Efficient respiration

Dinosaurs

Birds evolved from small, feathered-covered what? They are also the closest living relative to this animal.

Archaeopteryx

important traditional fossil, intermediate to birds and dinosaurs

Archaeopteryx lithographica

Related to theropods, group of saurischian dinosaurs

Caudipteryx zoui

Confuciusornis sanctus

Completely feathered lacking bony tail and toothed jaw

Mammals

This group of animals are:

• Endothermic

• Have hair

• Mammary glands that secrete milk

• Only vertebrates with specialized teeth

• Large brain contained in a large skull

  • Single lower jaw bone

  • Three inner ear bones

  • External ears

Rodentia

This mammalian order is comprise of about 2277 species including rats, mice, squirrels, beavers, and porcupines; plant eating; gnawing habit with two pairs of continually growing incisor teeth

Chiroptera

This mammalian order consists of about 1116 species including bats; insect or fruit eating; small; have ability to fly; navigate by sonar; nocturnal

Eulipotyphyla

This mammalian order consists of about 452 species including shrews, moles, and hedgehogs; insect eaters; primitive placental mammals

Primates

This mammalian order consists of about 404 species including monkeys, apes, and humans; opposable thumb, binocular vision; large brains

Carnivora

This mammalian order consists of about 286 species including cats, dogs, weasels, bears, seals, and sea lions; flesh-eating mammals; canine teeth

Artiodactyla

This mammalian order consists of about 240 species including deer, antelopes, cattle, sheep, goats, camels, and pigs; herbivorous hoofed mammals, usually with two toes, hippopotamus and others with four toes; many with horns or antlers

Diprotodontia

This mammalian order consists of about 143 species including kangaroos, koalas, opossums, and wombats; pouched mammals mainly found in Australia

Lagomorpha

This mammalian order consists of about 92 species including rabbits and hares; powerful hind legs; rodent-like teeth

Cetacea

This mammalian order consists of about 84 species including whales and dolphins; marine fishes or plankton feeders; front limbs modified into flippers; no hind legs; little hair except on snout

Perissodactyla

This mammalian order consists of about 18 species including horses, zebras, tapirs, and rhinoceroses; hoofed herbivorous mammals with odd number of toes, one (horses) or three (rhinos)

Monotremata

This mammalian order consists of about 5 species including duck-billed platypuses and echidna; egg-laying mammals found only in Australia and New Guinea

Proboscidea

This mammalian order consists of about 3 species one of which are elephants; long trunk; large upper incisors modified as tusks

sensory, camouflage, quills

Types of hair on mammals

biting, grinding, gnawing, tusks, grasping

Types of teeth in mammals

3 main groups of mammals

Subclass Prototheria- Order Monotremata

Sublcass Theria- Clade Metatheria

Subclass Theria- Clade Eutheria

Subclass Prototheria - Order Monotremata

Platypus and echidna lay eggs, lack placenta, poorly developed nipples

Subclass Theria -Clade Metatheria Marsupials

Marsupials:

• 7 orders

• Once widespread, now confined to Australia

• Opossum found in North America

• Very undeveloped young must make it to marsupium to finish development

Subclass Theria - Clade Eutheria

Placental mammals

• Long-lived complex placenta

• Prolonged gestation

Hominidae

This family includes humans (Homo sapiens) and related extinct species that are distinguished from apes by their bipedalism and increased brain size