Plant evolutionPlant evolution

• Proterozoic – Green algal evolution• Mid paleozoic – First land plants• Late paleozoic – Coal forests: early vascular

plants• Latest paleozoic – seed plants, early

Gymnosperms• Mesozoic – Gymnosperms (and reptiles) dominant• Late mesozoic – first flowering plants• Cenozoic – coevolution of flowering plants and

insect pollinators

Ancestral GreenAlgae Bryophytes Ferns & allies Gymnosperms Angiosperms

Embryos

Vascular tissue

Seeds

Flowers

Overview Overview of Plant of Plant

EvolutionEvolution

Bryophyte-like Bryophyte-like plants evolved plants evolved

from from Charophycean Charophycean Green AlgaeGreen Algae

Chara

ColeochaeteA Coleochaete B Parka (Ordovician)From Berkeley Time Machine

Seedless Vascular PlantsSeedless Vascular Plants

• Vascular tissue improves sporophyte efficiency

• Dominant plants from late Devonian through early Permian* Equatorial coal forests

Early Devonian landscape

Carboniferous (-300 my) coal forest model

Imagine a dragonfly Imagine a dragonfly with a wingspan of with a wingspan of

over 1 meterover 1 meter

Carboniferous forestCarboniferous forest

Devonian plant rootsDevonian plant roots

First seed plantsFirst seed plants

• Pregymnosperms• Early Permean• Pangea – dry, continental climates

Seed fern seedsSeed fern seeds

Trigonocarpus from Mazon Creek formation (Carboniferous)

Evolution of flower & fruitEvolution of flower & fruit

• First fossils: late Jurassic period of Mesozoic era

• Diversified during Cenozoic era

• Coevolution with pollinators

Oldest flowering plant fossilOldest flowering plant fossil

Fruit fossilFruit fossil

Primitive existing flowersPrimitive existing flowers