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Week6Sosorryfortheextremelateness,hadseriousissueswithinabilityto

accesszimbra.

LifeinSea,Terrestrialization

Lifeinsea:morestable,buoyancy,thermalbuffer,osmoticpressure,pH.

Greaterspeciesrichnessattropics

Photosythesislimitedtoupperlevelofsea

Beneaththis,detritovoresandpredatorsofdetritovores,exceptverydeep

communitiesatventsandcoldseepsbasedonchemosyntheticorganisms.

Extremevariationinhabitatofintertidalorganisms

Expansion:Initially,onlysediment-waterinterfacecolonized

Stromatolitesfirstreefs,thenArchaeocyatha(inCambrian,nowextinct),then

spongeandcorallinealgaereefs.

CoralreefsdominatefromOrdivician(460mya)tonow

Nekton(swimming)vsPlankton(floating)

Infauna(lateinfaunadestroysoriginalfossils),andstalkedandfreefloating

organisms.

ImportantPoints:Morespeciestodaythaneverbefore,butfewerphyla!

Diversityreboundstogreaterthaninitialrichnessaftermassextinctions

MostextantlifeoriginatedinCambrian

Marineorganismsdistributedalonggradients

Terrestrialization:

Sepkoskisfauna:Cambrian(primitivemollusks,trilobites,andcrinoids),Paleozoic

(cephlopods,corals,primitiveechinoderms),Modern(crustaceans,vertebrates,

bivalves.

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Importanceofcyanobacteria,inwaterinstromatolitesandonland(remember

crunchydesertcrust=cyanobacteria)

Lichens!Symbioticplant/fungithatbreakdownrocks,stabilizesoil.

Fungidecomposethings.Criticaltonitrogenfixation,nutrientcycling.

Plants:rememberphylogeny

Originalbareness,2dnatureofland,asplantsevolvedincreased3dimensionality

Mimicsevolutionofamphibiansininnovationofnotneedingwatertoreproduce

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Significanceofwindpollinationbygymnosperms

Angiosperms:usewind,water,animalsfordispersal

Wormsburrowdown,colonizeearth

Arthropodscolonizeeverything

TerrestrializationEmbryonicandamphibianlimbdevelopmentmimicsevolutionoflimbdevelopment

Maysupplementfossilrecord,whichisrelativelypoor.

Keyinnovation:amnioticegg

BhushanandMiserezpapers:BiomimeticsandBioengineering

Biomimetics:mimickingnature.Evolutionhasresultedinincidentalinnovations

usefulfortechnologyandhumansociety.Microandmacroscale.

Muchtolearnfrommanyorganisms(needtopreservethem)

Natureengineerssolutionstocomplexproblemsthattroublehumanstoday.

Janvierpaper:Terrestrialization

Needtoadaptto:gravity,UVlight,highO2levels,lackofwater,locomotion,

reproductionwithoutwater.

Transitionofplantsfromwatertolandclearerintermsoflivingtransitionalforms

forplantsthananimals,butfewtransitionalfossilsofplantsexists(difficulttopreserve)

Nocompletelyterrestrialorganismsseemstohavecompletelyre-adaptedtoaquaticlifestyle(exceptperhapsplanorbidsnails)

Problemswithconceptofconquestofland

Onlycertaintaxaeverterrestrialized,mostlyvertebrates,arthropods,

embryophytes,fungi.

Padolfipaper:Paleoecologyofcoralreefs.

Latitudinalrangelimitsforreefsvarywithclimate

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Reefsveryimportantinnichecreation(importanceof3dstructure).

Locationsoftopreefbiodiversityhavevariedovertime,butreefgrowthratenot

necessarilydependentondiversity

Anthropogeniceffects(suchasoverexploitation,pollutions,etc)onreefs

unprecedented,socoralvulnerabilitycannotbedetermined.

Coralsserveaspaleoproxiesofclimatechange:reefcoresrecordsurfacetemperatures,rainfall,riverdischarge