Animal Kingdom Vertebrates 6th Grade Science

Classification “Kings play chess on fine gold sets” Kingdom Animalia Phylum Chordata Class Mammalia Order Primate Family Homidea Genus Homo Species sapien

What is a Chordate? All chordates have 4 basic features that are present at some point during their life cycle Hollow Nerve Cord – Nerve cord in which nerves branch out at regular intervals Notochord – Long supporting rod that runs throughout body Pharyngeal Pouches/Gill Slits – Paired structures in throat Muscular Tail – Extends beyond anus Only 4-5% of animals are chordates Examples = Fish, Amphibians, Reptiles, Birds, Mammals

Chordate Cladogram Section 30-1 Mammals Birds Reptiles Amphibians Fishes Nonvertebrate chordates Invertebrate ancestor

The Generalized Structure of a Chordate Section 30-1 Muscle segments Tail Anus Pharyngeal pouches Mouth Hollow nerve cord Notochord

Vertebrates Vertebrates have an internal system of bones called an endoskeleton Ectotherms are cold-blooded animals whose body temperatures change as their environmental temperatures change, e.g. fish, amphibians, reptiles Endotherms are warm-blooded animals whose body temperatures do not change with changes in their surroundings, e.g., birds and mammals

Fish – Basic Facts Fish are ectotherms living in nearly every single aquatic habitat Fish are aquatic vertebrates characterized by fins, scales, and gills Fish were the first vertebrates to evolve some 500 million years ago during the Paleozoic era!! Fish bring in oxygen rich water through gills and remove oxygen poor water through gill slits; GILLS exchange carbon dioxide for oxygen Closed circulatory system with two chambered heart Fins help fish steer, balance, and move Scales cover and protect skin Swim bladder controls buoyancy Most are egg laying LARGEST GROUP OF VERTEBRATES!

Fish Classification Phylum: Chordata Subphyla: Classes: Urochordata -- sea squirts Cephalochordata -- lancelets Vertebrata -- vertebrates Classes: Agnatha -- lampreys and hagfishes Chondrichthyes -- sharks and rays Osteichthyes -- bony fishes

Sea Ray - Chondrichthyes Lamprey – Jawless Fish Catfish - Osteichthyes Whale Shark - Chondrichthyes

Osteichthyes Bony fishes ~ majority of fishes Three subclasses: lungfishes, lobe-finned fishes, and ray-finned fishes Have a skeleton made of bone; 95% of all fish Have a swim bladder or air sac to help control swimming depth Carp, sea horse, perch, etc Flexible skeleton allows for fast speeds Separate sexes, fertilization external in most Live-bearers include guppies, mollies, swordfish

Osteichthyes

Agnatha Agnatha Hagfishes and Lampreys Jawless fish w/ slit-like, toothed mouth; feed on dead or dying fish by drilling a hole and sucking the blood and insides from the animal Have mouths of soft tissue with no true teeth. Have no bones; Only vertebrates with no vertebral column as adults Breathe using gills Reproduce sexually (external fertilization) Two-chambered heart blood flow through body is slow, as most of pumping action is used to push blood through gills.

Chondrichthyes Sharks, Skates, and Rays (living fossils) Cartilaginous fish w/ skeleton of cartilage Paired fins for balance, swimming, and steering Evolution of jaws Sharks -- 6-20 rows of teeth, continually replaced Highly developed sensory systems extremely sensitive sense of smell lateral line system -- detects movement and vibrations in water (line of fluid-filled canals) Internal fertilization -- eggs kept inside body when young are released, they behave like mini-adults

Amphibian Classification Phylum: Chordata Class: Amphibia Order: Urodela -- salamanders and newts Anura -- frogs and toads Apoda -- legless caecilians

Groups of Amphibians Salamanders – Long bodies and tails Adults are carnivorous Usually live in moist woods Frogs and Toads – Lack tails Frogs have long legs and are usually tied to water Toads have shorter legs and not as closely tied to water Caecilians – Legless animals that burrow in moist soil Have fishlike scales

Spotted Salamander Poison Dart Frog Fire Bellied Toad Caecilian

Amphibian Characteristics Spend part of their lives on land and part in water, but nearly all rely on water for breeding Adaptations – adjustments for temperature Ectotherms -- body temperature changes with temperature of the surroundings Hibernation – inactivity during cold weather Estivation – inactivity during warm weather Three-chambered heart ~ skin very important as an organ for gas exchange

Amphibian Characteristics Endoskeleton made of bones to support body on land Lungs to breathe on land; also exchange oxygen and carbon dioxide through the skin Hearing and vision adapted to land life Long tongue captures insects for food Descendants of ancestral organisms that evolved some, not all, adaptations for life on land First appeared 360 million years ago

Amphibian Metamorphosis Hatched from eggs fertilized in water; tadpoles live in water and breathe through gills Land-function structures such as legs and lungs develop for land life

The Life Cycle of a Frog Section 30-3 Adult Frog Young Frog Adults are typically ready to breed in about one to two years. Young Frog Frog eggs are laid in water and undergo external fertilization. The eggs hatch into tadpoles a few days to several weeks later. Fertilized Eggs Tadpoles Tadpoles gradually grow limbs, lose their tails and gills, and become meat-eaters as they develop into terrestrial adults.

Section 30-3 Amphibians means “Double life” as larvae they live in adults they live on Water Land and have special adaptations such as Bones Lungs Ribs are that allow for that allow that provide Efficient movement Breathing air Support and protection are

Reptiles – Basic Facts Ectothermic animals that generally live whole lives on land Body plans vary, but all reptiles have: Dry, scaly skin – helps prevent loss of body water in dry environments Terrestrial eggs – first animals to develop amniotic eggs that didn’t need to be deposited in water Respire using lungs Internal Fertilization; Most are egg-laying Behavior controls body temp. (swimming, burrowing, basking, etc.) Closed circulatory system; double loop; Heart = two atria/one or two ventricles

Reptiles – Basic Facts Some reptiles, such as turtles, use a hard shell for protection; turtles eat insects, worms, fish, plants Some, such as alligators or crocodiles, live in or near water Some, such as lizards and snakes, use their tongues to smell their environment; no ears – feel vibrations on ground Reptile adaptations: Thick, dry skin covered with scales protects and reduces water loss Breathe using lungs Internal fertilization produces amniotic egg that nourishes and protects the young until they hatch, fully developed

Groups of Reptiles Lizards and Snakes Have legs & clawed toes (lizards) external ears, moveable eyelids Highly evolved specialized forms (venom) Crocodiles and Alligators Long, typically broad snout and squat appearance All are carnivorous Protective of young; carry hatchlings in their mouth Live in tropics and subtropics Alligators live in freshwater Crocodiles live in fresh or saltwater

Groups of Reptiles (con.) Turtles and Tortoises – All are shelled Turtles are aquatic; tortoises are terrestrial Tuatara – Primitive reptiles found on small, remote islands

Coral Snake Sea Turtle Galapagos Tortoise Tuatara

Nile Crocodile North American Alligator

Birds – Basic Facts Endothermic vertebrates that have two wings, two legs, a bill or beak, feathers, and lay eggs Nearly 10,000 modern bird species Birds are closely related to reptiles (scales on legs) Feathers separate birds from all other animal species Feathers provide insulation for warmth; can generate on body heat Beak/Bills adapted to type of food they eat Highly efficient respiratory system; lungs only exposed to Oxygen rich air Internal fertilization; amniotic eggs; many mate for life

Birds – Basic Facts Adaptations for flight: Strong, hollow bones High-energy diet Large, efficient heart and a specialized respiratory system Lungs with air sacs for efficiency and light weight Wing shape and surface area, and air speed and angle combine with wing movements to provide an upward push for flight Wing shape, area, and speed determine amount of lift produced!

Birds – Basic Facts Functions of Feathers Strong, lightweight contour feathers give adult birds their stream-lined shape and coloring Barbs: parallel strands off the main shaft Help bird steer in air or swim Attract mates or protect bird from predators Down feathers – insulating layer of fluffy feathers under contour feathers Feather care – preening adds oil for water-repellency; also closes breaks or gaps in feathers (oil gland found at base of tail)

Birds Section 31-2 have the following adaptations to flight Wings Feathers Strong chest muscles Efficient respiratory system Efficient circulatory system which are that also that power that provide that ensure Homologous to front limbs in other vertebrates Provide warmth Upward and downward wing strokes One-way flow of O2-rich air O2 distribution to body tissues

Groups of Birds More than thirty orders of birds Some of the most common Perching Birds – largest order; many are songbirds (sparrows, crows, cardinals, etc.) Birds of Prey – fierce predators with hooked bills; large talons (condors, hawks, owls, eagles, etc.) Herons & Relatives – Wade in aquatic habitats (storks, herons, cranes) Ostriches & Relatives – flightless birds move by running or swimming (ostriches, emus, etc.)

Purple Finch Stork Red-Tailed Hawk Emu

Mammals – Basic Facts Endothermic vertebrates with mammary glands and hair First true mammals appeared 220 million years ago Mammals flourished after dinosaurs became extinct – 65 million years ago Basic characteristics Hair Mammary glands – produce milk to nourish young Breathe air Four chambered heart Endotherms – can generate own body heat Internal fertilization; care for young Specialized teeth Herbivores: plant-eating animals with incisors for cutting and molars for grinding Carnivores: meat eaters with sharp canines for tearing flesh Omnivores: eat both plants and animals using a variety of teeth

Mammals – Basic Facts Body Systems Well developed lungs made of millions of microscopic sacs called alveoli, which enable the exchange of carbon dioxide and oxygen during breathing Large brain and complex nervous system Internal fertilization to form embryo Monotremes (platypus – lay eggs) Marsupials Placentals

Mammal Types Monotremes: lay eggs and lack nipples on mammary glands Marsupials: give birth to immature young that finish developing in a pouch, e.g., opossums, kangaroos, koalas, Tasmanian devils, and wallabies Placentals: develop from embryos connected to a placenta by an umbilical cord Placenta provides food and oxygen to embryo and removes its waste Time of development in uterus is called gestation period Humans: 280 days Mice and rats: 21 days Elephant: 616 days

Mammals Today More than 4,000 species of mammals exist on Earth today Found on every continent and in every climate Have a role in maintaining environmental balance Many mammals are endangered due to destruction of their habitat

Orders of Placental Mammals Section 32-2 Orders of Placental Mammals Order Insectivores Sirenians Cetaceans Chiropterans Rodents Characteristics Examples Long, narrow snouts, sharp claws Water-dwelling, slow-moving Live and breed in ocean, come to surface to breathe Winged, capable of true flight Single pair of long, curved incisor teeth in upper and lower jaws Shrews, hedgehogs, moles Manatees, dugongs Whales, dolphins Bats Mice, rats, voles, squirrels, beavers, porcupines, chinchillas

Orders of Placental Mammals Section 32-2 Orders of Placental Mammals Order Perissodactyls Carnivores Artiodactyls Proboscideans Characteristics Examples Hoofed, with an odd number of toes on each foot Sharp teeth and claws Hoofed, with an even number of toes on each foot Trunks Horses, tapirs, rhinoceroses, zebras Tigers, hyenas, dogs, foxes, bears, raccoons, walruses Cattle, sheep, goats, pigs, ibex, giraffes, hippopotami, camels Asian and African elephants, mastodons and mammoths

Orders of Placental Mammals Section 32-2 Orders of Placental Mammals Order Lagomorphs Xenarthrans Primates Characteristics Examples Two pairs of incisors in upper jaw, hind legs allow leaping No teeth (or very small teeth in the back of the jaw) Highly developed cerebrum and complex behaviors Snowshoe hares, rabbits Sloths, anteaters, armadillos Lemurs, tarsiers, apes, gibbons, macaques, humans