VERTEBRATES When dinosaurs (& others) roamed the Earth…

VERTEBRATES: Phylum Chordata GENERAL VERTEBRATE CHARACTERISTICS: Vertebrates = an animal with a backbone All vertebrates belong to the Phylum Chordata. Vertebrates live nearly everywhere (ocean, freshwater, land, air)

VERTEBRATES: Phylum Chordata They have an endoskeleton, including a skull, backbone and jointed appendages Vertebrates have a closed circulatory system with a chambered heart.

VERTEBRATES: Phylum Chordata Vertebrates have a complex nervous system They can be: Oviparous = egg birth (Ex. birds) Viviparous = live birth (Ex. humans) Ovoviviparous = egg live birth (Ex. snakes)

VERTEBRATES: Phylum Chordata The classes of vertebrates: Class AgnathaClass Reptilia Class ChondricthyesClass Aves Class OsteichthyesClass Mammalia Class Amphibia

VERTEBRATES: Phylum Chordata Terms to know: Ectothermic- an animal whose body temperature is determined by its environment. Endothermic- an animal that generates its own body heat.

CLASS AGNATHA Hagfish

CLASS AGNATHA Lampreys & hagfish These are the jawless fish They are slippery, eel-like animals with no scales They do not have fins Lamprey

CLASS AGNATHA Agnathans have a 2-chambered heart and are ectothermic. Their skeleton is comprised of cartilage. Emit slime for defense Hagfish slime

CLASS CHONDRICHTHYES

Sharks & rays This class includes animals with jaws and teeth Their skeleton is made of cartilage and they have paired fins. Shark

CLASS CHONDRICHTHYES These animals have a 2- chambered heart and are ectothermic. They live in salt water (ocean) Fertilization is internal Manta ray

CLASS CHONDRICHTHYES Sharks are covered with scales and have sharp spines They have a keen sense of smell and can sense vibrations made in the water miles away! Shark

CLASS CHONDRICHTHYES Shark Anatomy

CLASS CHONDRICHTHYES Rays have flattened, kite-like bodies and smooth skin.

CLASS OSTEICHTHYES

Largest class of vertebrates (over 29,000 species!!) Includes all fish like perch, bass, salmon, swordfish, etc. These are bony fish that have jaws. Swordfish

CLASS OSTEICHTHYES Bony fish have a 2- chambered heart Ectothermic They breathe using gills covered by a plate called an operculum This plate keeps unwanted water from entering the gills

CLASS OSTEICHTHYES Fish utilize a swim bladder, which is a gas-filled organ. By adjusting the volume of gas in the swim bladder, a fish can maintain the correct amount of buoyancy needed for a particular depth of water. Swim bladder

CLASS OSTEICHTHYES Bony fish utilize a lateral line system for detecting changes in water pressure and vibrations. They have both dorsal and anal fins that serve to keep the fish from rolling and help it stay straight in the water.

CLASS OSTEICHTHYES Fish also have a both pelvic and pectoral fins, which they use for balancing and turning. Their caudal fin propels them through the water. Reproduction: fertilization takes place externally.

CLASS OSTEICHTHYES Caudal Fin

CLASS AMPHIBIA

Amphibians include animals such as frogs, toads, salamanders and newts. Their name means “living 2 ways” so they live on land and in water. Salamander

CLASS AMPHIBIA They have a bony skeleton. Amphibians have a 3-chambered heart and are ectothermic. These animals evolved legs which they use for walking and swimming. Most larval forms have gills, but by adulthood the gills are replaced by lungs (think tadpole  frog)

CLASS AMPHIBIA Frog Life Cycle

CLASS AMPHIBIA Amphibians have thin, moist skin with no scales. This feature allows them to breathe through their skin ( or perform cutaneous respiration).

CLASS AMPHIBIA Amphibian fertilization is external (outside the body) and eggs require a wet environment. Frogs & toads are tailless, but salamanders & newts have tails. Most amphibians are carnivores. Newt

QUIZ ALERT! Study for an upcoming quiz next class over the Vertebrate notes we have covered thus far!

CLASS REPTILIA

This class includes animals like snakes, alligators, crocodiles, turtles and dinosaurs. Reptiles can complete their entire life cycle on land

CLASS REPTILIA Dinosaurs are extinct reptiles that are thought to have been eliminated when a huge meteor struck the Earth and blocked out the sun. Without sun for heat & food, dinosaurs began to die off and eventually became extinct.

CLASS REPTILIA The reptilian egg (called an amniotic egg) is adapted for land – it is water- tight and contains its own supply of water.

CLASS REPTILIA A reptile egg consists of the following: YOLK SAC- provides nutrients to baby ALLONTOIS- holds wastes products AMNION- keeps embryo moist & protects it from injury CHORION- outermost layer; lets oxygen in & keeps water in

CLASS REPTILIA Most reptiles have tough, dry, leathery skin covered in scales (snakes have scales but tend to have moist skin) Most have a 3- chambered heart, but some have 4

CLASS REPTILIA Reptiles use internal fertilization Their skeleton is made entirely of bone

CLASS REPTILIA They have lungs throughout their life Ectothermic (many often “sunbathe” to regulate their body temperature

CLASS REPTILIA Turtles (live in water) and tortoises (live on land) Bony shell is part of their skeleton Toothless, but jaws have sharp edges Are almost deaf, but sense of smell is well-developed.

CLASS REPTILIA: Lizards Lizards are covered in scales & shed their skin periodically They have moveable eyelids & an ear opening Most are carnivores

CLASS REPTILIA: Snakes Are covered with scales, smooth skin Eyes are always open (no eyelids) A transparent scale protects the eye All are carnivores

CLASS REPTILIA Snakes swallow their prey whole by unhinging their upper & lower jaws from each other. Their teeth slant backward to hold their prey & prevent it from escaping.

CLASS REPTILIA Very few species of snakes are poisonous (only 30% are). Poison works in 2 ways: Rattlesnakes, copperheads & cottonmouths: Venom affects the circulatory system causing blood clots & the destruction of capillaries

CLASS REPTILIA Cobras, sea snakes and coral snakes: Venom affects the nervous system and causes paralysis in its’ victims Coral snake

CLASS REPTILIA: Crocodilians Crocodiles have long, slender snouts and are more aggressive Their teeth show when their mouth is closed Crocodile skulls

CLASS REPTILIA Alligators have shorter, round snouts

CLASS REPTILIA All crocodilians have nostrils, ear openings and eyes set high atop their head (for floating in the water) Another feature they have in common is that they care for their young

CLASS REPTILIA Crocs vs. Gators

CLASS AVES

Class Aves includes all bird species Birds use feathers for flight & warmth Have hollow bones (pneumatic) which gives them a lightweight skeleton

CLASS AVES Birds have a beak, but no teeth They also have an efficient respiratory system and a four-chambered heart Endothermic Snowy owl

CLASS AVES Birds are oviparous (lay eggs) and they care for their young after they hatch They have a keen sense of vision and hearing. Use their oil glands on tail to waterproof their feathers. Grey heron

CLASS AVES Bird feet are covered with scales and some have webbed feet for swimming (think ducks) Feet do not have nerves or blood vessels so they can’t feel cold water Mallard

CLASS AVES Some birds have lost the ability to fly, like penguins & ostriches Birds give birth to an amniotic egg that must be kept warm before it hatches.

CLASS MAMMALIA

Mammals include all animals that have hair, which they may use for insulation, camouflage, defense and sensory functions Porcupine

CLASS MAMMALIA Female mammals have mammary glands, which they use to nurse & care for their young. Mammals have diverse and specialized teeth that vary depending on the their diet. Sloth

CLASS MAMMALIA Mammals are endothermic They have a 4- chambered heart Use a diaphragm to assist them with breathing. River otter

Mammals have 3 modes of reproduction depending on what kind of animal they are: Monotremes Marsupials Placentals CLASS MAMMALIA

MONOTREMES: Lay eggs (oviparous) Example: platypus

CLASS MAMMALIA MARSUPIALS: This group of mammals includes kangaroos, koalas and opossums. Koala

CLASS MAMMALIA Gestation period is very short. Newborns are born blind, helpless and small. Must climb into and complete develop- ment in their mother’s pouch.

CLASS MAMMALIA PLACENTALS: Placental offspring stay in the uterus until development is complete. They receive nourishment via the placenta.

CLASS MAMMALIA The gestation of placentals is long Most mammals are placental

CLASS MAMMALIA Levels of Classification Kingdom  Phylum Class –Order Family Genus Species

CLASS MAMMALIA Orders of Mammals Order Rodentia:  Mice, rats, squirrels, porcupines & guinea pigs Order Chiroptera:  Bats Order Insectivora:  Shrews, moles and hedgehogs

CLASS MAMMALIA Orders of Mammals Order Carnivora:  Bears, wolves, lions, skunks, raccoons Order Primates:  Monkeys, apes, humans Order Artiodactyla:  Pigs, camels, deer, cattle, sheep

CLASS MAMMALIA Orders of Mammals Order Cetacea:  Whales and dolphins Order Lagomorpha:  Rabbits and hares Order Pinnipedia:  Seals, sea lions, walruses

CLASS MAMMALIA Orders of Mammals Order Edentata:  Anteaters, armadillos Order Macroscelidea:  Elephant shrews Order Perissodactyla:  Horses and zebras

CLASS MAMMALIA Orders of Mammals Order Scandentia:  Tree shrews Order Pholidota:  Pangolins Order Hyracoidea:  Hyraxes

CLASS MAMMALIA Orders of Mammals Order Sirenia:  Manatees and dugongs Order Proboscidea:  Elephants

CLASS MAMMALIA Orders of Mammals Order Dermoptera:  Flying lemurs Order Tubulidentata:  Aardvarks