1Land Plant Evolution:Land Plant Evolution:Algae to AngiospermsAlgae to AngiospermsThe greatest adaptive radiation . . .The greatest adaptive radiation . . .•• is the is the largest radiationlargest radiationof plantsof plants•• involves series of involves series ofdramatic adaptations todramatic adaptations tothe problem of living onthe problem of living onland and being non-land and being non-motilemotile•• exhibits successive exhibits successiverounds of speciation androunds of speciation andsubsequent extinctionsubsequent extinction•• sets the stage for the sets the stage for thedevelopment of a land-development of a land-based ecosystem withbased ecosystem withfungi and animalsfungi and animals. . . a nearly 500 million year story. . . a nearly 500 million year story. . . . . . for the evolution of for the evolution of Hordeum Hordeum andand Humulus Humulus. . . a nearly 500 million year wait. . . a nearly 500 million year waitLand Plant Evolution:Land Plant Evolution:Algae to AngiospermsAlgae to AngiospermsThe greatest adaptive radiation . . .The greatest adaptive radiation . . .•• know the know the basic extant land plant lineagesbasic extant land plant lineages today today•• understand the general (not the details) understand the general (not the details) series of events andseries of events andtimingtiming of the rise and fall of of the rise and fall of extinct land plant lineagesextinct land plant lineages•• know some of the know some of the adaptations for land plant lifeadaptations for land plant life that arose from that arose fromOrdovician to DevonianOrdovician to Devonian•• understand the basic arguments on the understand the basic arguments on the 4 phylogenetic issues4 phylogenetic issuesrelating to land plant evolutionrelating to land plant evolution••Ancestors of land plantsAncestors of land plants••Base of land plantsBase of land plants••Base of vascular plantsBase of vascular plants••Relationships among seed plantsRelationships among seed plantsAncestors of Land PlantsAncestors of Land PlantsGreen Plants are hereGreen Plants are here•• land plantsland plants are in a larger are in a largerlineage of green plants withinlineage of green plants withinPlantaePlantae•• a singlea single endosymbiotic endosymbiotic eventeventgave rise to plastidsgave rise to plastids•• land plants are derived from land plants are derived fromthe green algae lineagethe green algae lineage2Bryophyta Bryophyta - bryophytes - bryophytes •• 16,000 species16,000 species•• nonvascular plants, primitive land plantsnonvascular plants, primitive land plants•• gametophyte dominant gametophyte dominant•• comprising 3 main groups (often 3 phyla) comprising 3 main groups (often 3 phyla)liverwortsliverwortsmossesmosseshornwortshornwortsExtant Land PlantsExtant Land PlantsLycopodiophyta Lycopodiophyta - - lycopods lycopods •• 1,150 species 1,150 species•• vascular plants, primitive vascular plants vascular plants, primitive vascular plants•• sporophyte sporophyte dominant; freedominant; free sporing sporing•• comprising 3 familiescomprising 3 familiesspikemossspikemossquillwortquillwortclub mossclub mossExtant Land PlantsExtant Land PlantsEquisetophyta Equisetophyta - horsetails, scouring rushes - horsetails, scouring rushes •• 15 species in 15 species in EquisetumEquisetum•• vascular plants, reduced leaves, terminal vascular plants, reduced leaves, terminalsporangiasporangia•• sporophyte sporophyte dominant; free dominant; free sporingsporingExtant Land PlantsExtant Land PlantsPsilophyta Psilophyta - whisk ferns - whisk ferns •• 6 species in two genera 6 species in two genera•• vascular plants, leafless green stemmed, lateral vascular plants, leafless green stemmed, lateralsporangiasporangia•• once considered most primitive extant land plant once considered most primitive extant land plantExtant Land PlantsExtant Land Plants3Polypodiophyta Polypodiophyta - ferns - ferns •• 11,000 species 11,000 species•• diverse in habit and habitat diverse in habit and habitat•• spores produced in specialized sporangia spores produced in specialized sporangiaExtant Land PlantsExtant Land PlantsginkgoginkgoExtant Land PlantsExtant Land PlantsPinophyta Pinophyta - gymnosperms - gymnosperms •• 870 species 870 species•• seed plants but seeds naked or seed plants but seeds naked orexposedexposed•• often divided into 4 phyla often divided into 4 phylacycadscycadsExtant Land PlantsExtant Land PlantsPinophyta Pinophyta - gymnosperms - gymnosperms •• 870 species 870 species•• seed plants but seeds naked or seed plants but seeds naked orexposedexposed•• often divided into 4 phyla often divided into 4 phylaconifersconifersExtant Land PlantsExtant Land PlantsPinophyta Pinophyta - gymnosperms - gymnosperms •• 870 species 870 species•• seed plants but seeds naked or seed plants but seeds naked orexposedexposed•• often divided into 4 phyla often divided into 4 phyla4Pinophyta Pinophyta - gymnosperms - gymnosperms •• 870 species 870 species•• seed plants but seeds naked or seed plants but seeds naked orexposedexposed•• often divided into 4 phyla often divided into 4 phylagnetophytesgnetophytesExtant Land PlantsExtant Land PlantsMagnoliophyta Magnoliophyta - angiosperms, flowering plants - angiosperms, flowering plants •• 275,000 species 275,000 species•• tremendous adaptive radiation on land tremendous adaptive radiation on land•• seed plants with seeds encased in ovary seed plants with seeds encased in ovary•• flowers a flowers a ““key innovationkey innovation””Extant Land PlantsExtant Land PlantsEarth TimeEarth TimeAge of the earth = 1 calendar yearAge of the earth = 1 calendar year4.6 billion years = 365 days 4.6 billion years = 365 days Earth forms at 4.6Earth forms at 4.6 bya bya= January 1, 12:00 a.m.= January 1, 12:00 a.m.A different perspective beforeA different perspective beforetaking a look at the rise and falltaking a look at the rise and fallof land plant lineages throughof land plant lineages throughtime . . .time . . .Earth TimeEarth TimeAge of the earth = 1 calendar yearAge of the earth = 1 calendar year4.6 billion years = 365 days 4.6 billion years = 365 days First evidence of lifeFirst evidence of life - 3.8 - 3.8 byabyaOldest fossils - 3.5 Oldest fossils -