PLANT/ANIMAL EVOLUTION

PERIOD

M.Y.A.

PLANT EVOLUTION

ANIMAL EVOLUTION

Cenozoic Era

present

Angiosperms Dominate Land (decrease in number of species)

Age of Mammals

Quaternary

2

(dominance of land by angiosperms; increase in number of species of herbaceous plants; phytoplankton continue to dominate water)

(dominance of land by mammals and insects; dominance of water by bony fishes & zooplankton)

Tertiary

65

(dominance of land by angiosperms; increase in number of species of herbaceous plants; Phytoplankton continue to dominate water)

(dominance of land by mammals and insects; dominance of water by bony fishes & zooplankton)

Mesozoic Era

.

Gymnosperms Dominate Land; Phytoplankton continue to dominate water)

Age of Dinosaurs/Age of Reptiles; Bony fishes & zooplankton continue to dominate water

Cretaceous

138

Angiosperms spread

Dinosaurs become extinct

Jurassic

205

First Angiosperms (flowers) appear; gymnosperm forests dominate land

First mammals & birds appear; dinosaurs & insects dominate land

Triassic

240

Gymnosperms & ferns dominate land

First dinosaurs appear

Paleozoic Era

240

.

.

Permian

290

Seedless vascular forests decline as gymnosperms appear. Females produce eggs, green branches are sporophytes, pine cones (gametophyte) sex can be done without water

Amphibians decline as reptiles appear; arthropods abundant

Carboniferous

360

AGE OF GREAT COAL FORMING FORESTS. Seedless vascular plants dominate land; phytoplankton continue to dominate water

AGE OF AMPHIBIANS (our ancestors). Arthropods share dominance with amphibians on land; bony fishes & zooplankton continue to dominate water

Devonian

360

Expansion of seedless vascular plants; swamp forests form

First land animals; arthropods (insects, crabs, spirders) followed by amphibians

Silurian

410

Seedless vascular plants appear (club moss, ferns - produce spores, horsetail)

AGE OF FISHES. Fishes explode in diversity; share dominance of water with zooplankton

Ordovician

435

Bryophytes appear on land (liverwarts, gammeteophyte dominate generation)

AGE OF INVERTEBRATES. First fishes appear; invertebrates & protozoans dominate the seas

Cambrian

505

Algae explodes in diversity (no plants). Phytoplankton dominate the water

AGE OF INVERTEBRATES. Trilobites abundant, invertebrates & protozoans dominate the water; no life on land

Proterozoic Era

570 - 800

First multicellular organisms appear; first sexual reproduction; plankton continue to dominate the water; no life on land

Archean Era

2,500 - 3,900

Plankton (Moneras) dominate the water; no life on land

DEFINITION OF TERMS

Dominance - showing the greatest increase in number of species and number of offspring surviving; occupying the greatest diversity of habitats; showing the greatest success in defense against predators and competitors; and showing the capacity to exploit the greatest amounts and kinds of food.

Phytoplankton - an aquatic community of floating or weakly

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ŠV. Beth Kuser Olsen 1997