| Taxon (Class for most groups below) | Characteristics and major groups | Links to University of California at Berkeley | Links to Tree of Life Web Page | Examples of Organisms |
| Agnatha - lampreys (marine and freshawater) and hagfishes (marine) | jawless fishes (polyphyletic group) | |||
| Placoderms | jawed fishes with paired fins, heavily armored fossil group of fish | Placodermi | ||
| Chrondrichthyes - sharks, skates, rays | cartliaginous fishes, bony teeth, evidence of gradual evolution of a jaw from structures supporting gills | Chrondrichthyes | ||
| Osteichthyes - bony fishes | bony fishes, swim bladder,
lateral line system
Major groups: Actinopterygii - Ray-finned Fishes - modern fishes Sarcopterygii: Lobe-finned fish - bottom dwellers, muscular fins probably used for walking on ocean floor
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Actinopterygii - Ray-finned Fishes
Sarcopterygii: Lobe-finned fishes Coelocanths |
| Origin of Tetrapods | Hypothetical evolution of amphibians from fish | Tetrapoda | ||
| Amphibia |
frogs, toads, salamanders, apodans (snake-like amphibians), must spend part of their early development in water, first terrestrial vertebrates, legs for support, lungs and skin for gas exchange, restricted to development in water, also need to keep wet outer surface for gas exchange Major Groups
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Amphibia | Living Amphibians | |
| Origin of the amniotes and amniote egg | amniote egg gives vertebrates freedom to colonize entire terrestrial environment, egg has 2 internal membranes - chorion and amnion, encloses the ancestral pool | Amniote Egg | Amniota | |
| Reptilia |
internal fertilization, deeper skull, long and flexible neck, scales to prevent water loss and the amniote egg, development occurs inside egg that contains ancestral pool, gave rise to many different groups Major Groups
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Anapsida (turtles and their kin) Euryapsida |
Anapsida |
Anapsida (turtles and allies) Synapsida (contains mammal-like reptiles) Diapsida (modern reptiles, Pterosaurs and dinosaurs)
Euryapsida (Pleiosaurs, Icthyosaurs and allies) |
| Aves |
feathers, air sacs, keeled sternum, gizzard (no teeth), hollow bones Major Groups - see examples |
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Arhcaeopteryx - missing link to the Theropod ancestors Ratites
Sphenisciformes (Penguins) Gaviiformes (Loons) Podicipedformes (Grebes) Pelecaniformes (Pelicans and allies) Phoenicopteriformes (Flamingoes) Ciconiiformes (Herons, storks and allies) Anseriformes (Ducks, Geese) Falconiformes (Hawks, Falcons) Galliformes (Chicken-like birds) Gruiformes (Coot, Cranes and allies) Charadriiformes (Gulls, shorebirds and allies) Columbiformes (Doves, Pigeons and allies) Psittaciformes (Parrots) Cuculiformes (Cuckoos) Strigiformes (Owls) Caprimulgiformes (Goatsuckers and allies) Apodiformes (Swifts and Hummingbirds) Trogoniformes (Trogons) Coraciiformes (Rollers, Kingfishers and allies) Piciformes (Woodpeckers and allies) Passeriformes (Songbirds)
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| Mammalia | hair, mammary glands and 4 chambered
heart, differentiation among teeth
Monotremes - egg-laying mammals Marsupials - joey, completes development in marsupium Placentals - complete development in womb |
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Marsupials Placentals
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| Primates | Prosimii - Arboreal, Primitive forms
Anthropoids - Ape-like primates
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Primates |
Prosimians Anthropoids |
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| Human Evolution | Australopithecus - fossils
from Africa 5-4 MYA
Homo habilis - fossils from Africa 2.5-1.6 MYA H. erectus (migrates out of Africa into Asia and Europe) - 1.8 MYA - 500,000 Years ago H. sapiens - appears outside Africa 500,00 - 100,000 Years ago |
Hominid Speices and Timeline | ||
| Two Hypotheses | 1) Multiregional - several populations
of H. sapiens evolve in different regions of the world from H. erectus (after
H. erectus left Africa 1 - 2 mya)
2) Out of Africa: H. sapiens evolved from a second migration out of Africa about 100,000 years ago |
