ANIMAL EVOLUTION

What is an animal? Eukaryotic Multicellular Heterotrophic Organized

What is

Animal Invertebrates Eukaryotes Multicellular Heterotrophic No Vertebrate Backbone Central Notocord

Invertebrate Animals

Tied to the water! Living in the water is EASY!

What do all animals require to survive? Water Oxygen Food Ability to reproduce

No Symmetry, 2 cell layers (endoderm, ectoderm)

SPONGES

How do they get food? Oxygen? Reproduce?

TISSUE LAYERS

PHYLUM: Cnidaria No true tissue Marine ex. Jellyfish, hydra, coral, sea anemone

Nerve Net Tentacles with stinging cells

Still tied to the water! Radial Symmetry 2 cell layers (endoderm, ectoderm)

Corals

Sea Anenomes

Symbiotic Relationships

BRAIN CORAL

PHYLUM: Echinodermata Means: Spiny Skin Radial Symmetry Sexual and Asexual Seastar, sea urchin, sand dollar

Sea Urchins & Sand Dollars How do they get food? Oxygen? Reproduce?

Bilateral 3 cell layers (endoderm, mesoderm, ectoderm) Getting larger! Still in the water!

Becoming Bilateral! Cephalization

PHYLUM: Mollusca Calcium carbonate shell Soft body: mantle ex. Snails, clams, oysters

How do they get food? Oxygen? Reproduce?

PHYLUM: Nematoda Roundworm Symmetrical Notocord One-way digestive system

ex. Ringworm, heartworm

Hookworm parasites

PHYLUM: Annelida Segmented worm One-way digestive tract ex. Earthworm, leeches

How do they get food? Oxygen? Reproduce?

PHYLUM: Platyhelminthes Plat=Flat Flatworms Aquatic or semi-aquatic bilateral

Tapeworms

PHYLUM: Arthropoda Body Segments Exoskeleton made of what? Chitin=carbo Jointed appendages

CLASS: Insecta PHYLUM: Arthropoda 6 legs 3 body segments wings ex. Bee, grasshopper How do they get food? Oxygen? Reproduce?

CLASS: Arachnida PHYLUM: Arthropoda 8 legs (4 pairs) 2 body segments No antennae ex. Spiders, ticks, mites, scorpions

CLASS: Crusteacean PHYLUM: Arthropoda Breath through gills 2 pair of anntenae 2 body segments, 5 pairs legs mostly marine ex. Shrimp, lobster, pillbug

PHYLUM: Chordata Has a notochord at some stage of development (cartilage) Dorsal nerve cord Ventral heart

All vertebrates are chordates. NOT all chordates are vertebrates. Diffusion PHYLUM: Chordata

Finally, moving to land?

Phylum: Chordata Subphylum: Vertebrate Notochord replaced by vertebrate backbone in embryo Specialized muscle system Internal skeleton CNS w/ brain Appendages for locomotion

3 Classes of Fish Phylum:Chordata, Subphylum:Vertebrate Fins Ectotherms: body temp. according to environment LAND HO! WELL, NO LAND YET!!!! How do they get food? Oxygen?

Subphylum: Agnatha Jawless Fish Sucker mouth No scales; slimy skin Gills not covered Cartilage skeleton Ex. Lamprey & hagfish

Subphylum: Chondrichthyes Cartilage fish Sharks, rays & skates Tooth-like scales Hinged jaw Gills not covered

Subphylum: Osteichthyes Bony fish Eel, salmon, trout Hinged jaw Flat scales Covered gills

Reproduce? External Fertilization External Development

LAND HO! NOW!!!!

Problems with living on land! Reproduction Gas exhange Gravity Movement Dessication Temperature (winter) Transporting nutrients throughout body

Class: Amphibian Immature:gills Adult: lungs Thin moist skin

Reproduction? External Fertilization External Development

Class: Reptiles Dry scaly skin Ectotherm Lungs Internal Fertilization Extenal Development

METAMORPHOSISMETAMORPHOSIS

Reptiles Internal Fertilization External Development

Endo/ecto-therm

Class: Aves Birds Scales on legs Endotherms Feathers for insulation Thin bones Lungs Internal Fertilization External Development

Class: Mammals Care for young Feed milk Endotherms Hair or fur Lungs Developed brain Internal Fertilization & Development

65/ 65/ eats/2010/01/06/fossil-footprints-show- animals-adventured-onto-land-earlier- than-thought /