The Vertebrate Animals Animals that have bones that form a backbone or spinal column.

All Vertebrates are Chordates Phylum chordata! Chordates ALL have 4 characteristics sometime during their lives a notochord nerve cord gill slits a tail

Chordate Characteristics

99% of chordates are vertebrates - Characteristics of Vertebrates Bilateral Symmetry with 2 pairs of appendages Cephalization (sense organs concentrated in a head region) True body cavity closed circulatory system. Endoskeleton including a vertebral column Well developed body systems – internal organs

Characteristics of Vertebrates Vertebral Column Replaces notochord Protects dorsal nerve chord Built from cartilage or bone Strong, flexible rod that muscles pull against while swimming or running. Separate vertebrate enhance ability to move quickly

Characteristics of Vertebrates Neural Crest A group of cells that develop from the nerve chord Features develop from neural crest: Brain and skull Certain sense organs Nerve fibers

Comparative Numbers of Species

Classes of Vertebrates Fish Jawless fish Cartilaginous Fishes Bony Fish Amphibians Reptiles Birds Mammals

Characteristics of Fish Activity pages 822-827

Characteristics of Fish Jaws Allow them to prey on larger range of animals More powerful Grasp prey and quickly crush them Biting defense against predators

Characteristics of Fish Paired fins Give stability Reduce the chances of rolling to side Allow for precise steering Scales Made of bone Thin and flexible 4 types-ctenoid, cycloid, placoid & ganoid

Characteristics of Fish Gills Where oxygen in water diffuses into blood Composed of Thin filaments Lamellae – have many blood vessels Flow of blood is opposite the flow of water Operculum – moveable flap that covers gills Aid in pumping water

Characteristics of Fish Circulation Blood moves in a one way loop Heart  Gills  Body (deliver Oxygen) Heart – 2 chambers Atrium – receives blood from body Ventricle – pumps blood to gills

Characteristics of Fish Feeding & Digestion Swallow food whole Esophagus to stomach Some have pyloric ceca Small pouches secrete enzymes Liver, pancreas and gallbladder add digestive juices Must get amino acids from food

Characteristics of Fish Excretion Wastes filtered by kidneys Nephron – main filtering unit Some wastes excreted by gills Must balance salt and water in both freshwater and salt water fish

Characteristics of Fish Brain and Senses Receptors to sense smell – detect chemicals Color vision Lateral line Detect the slightest movements Keep upright and balanced

Characteristics of Fish Reproduction Majority – external fertilization Spawning – release gamates near each other in water. Produce millions of egg No care by parent fish Male sergeant fish Prey to some animals Sharks – internal fertilization

Characteristics of Fish Nemo clip

Characteristics of Fish Movement Streamlined shape Mucus lubricates body – reduces friction Fins – steer Swim bladder – gas-filled space Control depth Move in an s-shaped pattern

Classes of Fish Jawless fish Cartilaginous Fishes Bony Fish

Class Agnatha - Jawless Fish Primitive, no paired fins no bone, all cartilage Lamprey – a parasite Hagfish – scavenger, also called slime eel. Produce slime when threatened

Class Agnatha – Jawless Fish

Class Chondrichthyes - Cartilage Fish Sharks, skates, rays - 750 species Jaws with teeth Possesses 5-7 gills No swim bladder Heteroceral tail Massive liver (up to half body weight) Lateral line skin with tooth-like scales

Class Chondrichthyes Cartilage Fish                                                                  

Class Placodermi Totally fossil, early jawed fishes; Bony armor usually present around head-trunk, generally flattened body, tend to be bottom-adapted with eyes rather dorsal (other various designs); No true teeth Notochord persistent, un-constricted.

Class Osteichthyes – Bony Fish 20-30,000 species Appeared 400 million years ago Bony skeleton – paired fins Lateral line 4 paired gilled arches and gill cover Most lay eggs Eyes usually on the side of the head

Class Osteichthyes – Bony Fish Homocercal tail Cold blooded, swim bladder, flat scales 3 types of scales

Basic Fish Structure

Bony Fish

Fish Diversity

White mouthed morey Achilles tang trumpetfish Domino damsel Trigger (Humu) White mouthed morey Porcupine Dwarf moray Achilles tang trumpetfish

Walleye, Northerns, Perch, Bass, Bullheads, Trout, etc.

Class Osteichthyes, the bony fishes Subclass Actinopterygii, the ray-finned fishes Superorder Chondrostei, the primitive ray-finned bony fishes: sturgeons, paddlefish, and bichirs Superorder Holostei or Neopterygii, the intermediate ray-finned fishes: gars and the bowfin Superorder Teleostei or Neopterygii, the advanced bony fishes: herring, salmon, perch. Subclass Crossopterygii, the coelacanth Subclass Dipnoi or Dipneusti, the lungfishes

Coelacanth Thought to be extinct 80 million years ago Found in 1938 off the coast of the Comoro Islands

Coelacanth Anatomy Unsegmented notochord Rostral organ Intercranial joint Fat filled swim bladder Ovoviviparous

Anatomical Similarities: To sharks To Fish Spiral valve intestine Give birth to live young Long cartilaginous tube instead of backbone bony head teeth scales

The coelacanth’s phylogenetic classification remains inconclusive Anatomical Similarities to Tetrapods: fat filled lung fleshy lobed-fins circulatory system inner ear intracranial joint- a feature once found in ancient frogs The coelacanth’s phylogenetic classification remains inconclusive

Class Amphibia

Class Amphibia 2000 species, appeared 350 million years ago. Cold-blooded, moist skin, lungs, no claws Lay jellylike eggs - Returns to water to breed 90% are frogs and toads Some are toxic – poison dart frog Life cycle includes a larval stage - metamorphosis

Class Amphibia Metamorphosis

Amphibians Mudpuppy newt (salamander) salamander Poison arrow frog Rana cancrivora Coqui

Amphibians

Class Amphibia “Canaries in the Coal Mine” Habitat destruction Introduced species Pollution Pesticide use Diseases Over-harvesting Climate change Increased UV radiation

Class Amphibia One-third of the world's 5,918 known amphibian species are classified as threatened with extinction. More than 120 species have likely gone extinct since 1980.

Frog Dissection

Class Reptila

Reptiles 6500 species, appeared 300 mya Cold-blooded 3 chambered heart Body covered with scales. Dry skin Carnivorous Breathe with lungs Include crocodilians, lizards and snakes, turtles

Reptiles Hard shelled eggs, internal fertilization – NO metamorphosis Amniotic Eggs (4 layers) Yolk sac (food) allantois (waste) amnion (fluid) chorion (gases)

Reptiles

Class Reptilia Saltwater crocodile Marine iguana Marine turtle Sea snake

Class AVES - birds

Class Aves - Birds 8600 species, appeared 130 million years ago. Warm blooded, 4 chambered heart Sizes (less than a pound to over 300#) Eggs – hard egg shell Lungs have air sacs

The skeletons of birds have several adaptations that make them light, flexible, but strong. The bones are honeycombed to reduce weight without sacrificing much strength.

AVES - Birds Adaptations for flight. Many migrate feathers – feathered dinosaurs crop oil glands hollow bones fused skeleton Many migrate

Birds

The Geese Return Aldo Leopold Identification of Flying Birds

Class mammalia

Mammals First appeared 180 million years ago 4500 species, most are placental. 2 primitive orders; monotremes and marsupials

Mammals Diaphragm Hair or fur Mammary glands Lips Different kinds of teeth External ears

Warm Blooded Animals Regulate body temperature Have insulation Produce heat Need larger amounts of food Have larger oxygen needs Hypothalamus (brain part controlling temp.)

Class Mammalia Subclasses Protheria- echidna & platypus Metatheria- marsupial Eutheria- true mammals A Guide to characteristics of Class Mammalia The Class Mammalia is well represented in Southern Africa. There are 293 species of land mammals and 37 species of marine mammals in the Southern African subregion. That is 330 of the around 5000 mammal species found on Earth! Class Mammalia -- all mammals share three characteristics not found in other animals: 3 middle ear bones; hair; and the production of milk by modified sweat glands called mammary glands. Mammals hear sounds after they are transmitted from the outside world to their inner ears by a chain of three bones, the malleus, incus, and stapes. Two of these, the malleus and incus, are derived from bones involved in jaw articulation in most other vertebrates. Mammals have hair. Adults of some species lose most of their hair, but hair is present at least during some phase of the ontogeny of all species. Mammalian hair, made of a protein called keratin, serves at least four functions. First, it slows the exchange of heat with the environment (insulation). Second, specialized hairs (whiskers or "vibrissae") have a sensory function, letting the owner know when it is in contact with an object in its external environment. These hairs are often richly innervated and well-supplied with muscles that control their position. Third, through their color and pattern, hairs affect the appearance of a mammal. They may serve to camouflage, to announce the presence of especially good defense systems (for example, the conspicuous color pattern of a skunk is a warning to predators), or to communicate social information (for example, threats, such as the erect hair on the back of a wolf; sex, such as the different colors of male and female capuchin monkeys; presence of danger, such as the white underside of the tail of a whitetailed deer). Fourth, hair provides some protection, either simply by providing an additional protective layer (against abrasion or sunburn, for example) or by taking on the form of dangerous spines that deter predators (porcupines, spiny rats, others). Mammals feed their newborn young with milk, a substance rich in fats and protein that is produced by modified sweat glands called mammary glands. These glands, which take a variety of shapes, are usually located on the ventral surface of females along paths that run from the chest region to the groin. They vary in number from two (one right, one left, as in humans) to a dozen or more. Other characteristics found in most mammals include highly differentiated teeth; teeth are replaced just once during an individual's life (this condition is called diphyodonty, and the first set is called "milk teeth); a lower jaw made up of a single bone, the dentary; four-chambered hearts, a secondary palate separating air and food passages in the mouth; a muscular diaphragm separating thoracic and abdominal cavities; highly developed brain; endothermy and homeothermy; separate sexes with the sex of an embryo being determined by the presence of a Y or 2 X chromosomes; and internal fertilization. The Class Mammalia includes around 5000 species placed in 26 orders (systematists do not yet agree on the exact number or on how some orders are related to others). Mammals can be found in all continents and seas. In part because of their high metabolic rates (associated with homeothermy and endothermy), they often play an ecological role that seems disproportionately large compared to their numerical abundance. Subclass Prototheria - Not represented in southern Africa Order Monotremata -- Monotremes: platypus and echidnas Subclass Metatheria (marsupials) - Not represented in southern Africa Order Didelphimorphia Order Paucituberculata Order Microbiotheria Order Dasyuromorphia Order Peramelemorphia Order Notoryctemorphia Order Diprotodontia Subclass Eutheria (placentals) Order Insectivora -- Insectivores: shrews, moles, hedgehogs, tenrecs, etc. Order Macroscelidea -- elephant shrews Order Scandentia -- tree shrews Order Dermoptera -- colugos Order Chiroptera --bats Order Primates --primates Order Xenarthra -- edentates; sloths, armadillos and anteaters Order Pholidota -- pangolins Order Lagomorpha -- rabbits and pikas Order Rodentia -- rodents Order Cetacea -- whales, dolphins, and porpoises Order Carnivora -- carnivores Order Tubulidentata -- aardvark Order Proboscidea -- elephants Order Hyracoidea -- hyraxes Order Sirenia -- dugongs and manatees Order Perissodactyla -- horses, rhinos, tapirs Order Artiodactyla -- antelope, giraffe, camels, pigs, hippos, etc.

Prototherians (Monotremes): Cretaceous-Recent Egg-laying, aquatic predators on arthropods and worms Milk oozes from the skin (no breasts). Hair Ear bones shift from lower jaw to skull during embryonic development. Electroreception

Metatheria (Marsupials): Cretaceous-Recent Pouched mammals. Born as gross little embryos.  Crawl into pouch, attach to nipple, and develop. Cretaceous ones were fairly opossum-like in their ecology.  Later ones are more diverse. Today, they are most diverse on Australia and South America. They share complex type of molar tooth shape with Placental mammals.

(a) A young brushtail possum

Eutheria (Placentals): Cretaceous-Recent Nourish their young internally with a placenta Placentals give birth to offspring that are more "adult" like and independent. Cretaceous ones were shrew-like in their ecology.  Later placentals are spectacularly diverse.

Copyright © 2002 Pearson Education, Inc Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

Copyright © 2002 Pearson Education, Inc Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

Copyright © 2002 Pearson Education, Inc Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

Copyright © 2002 Pearson Education, Inc Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings

The Vertebrate Animals