BobPaineisnearly2metrestallandhasapowerfulgrip.Theochreseastar,however,hasfivesucker-linedarmsandcanspanhalfametre.SowhenPainetriedtoprisethecreaturesofftherocksalongthePacificcoast,hefoundthathisbrutestrengthsimplywasn’tenough.Intheend,heresortedtoacrowbar.Then,oncehehadleveredtheanimalsup,hehurledthemouttoseaashardashecould.“Yougetprettygoodatthrowingstarfishintodeeperwater,”hesays.Itwasaritualthatbeganin1963,onan8-metrestretchofshoreinMakahBay,Washington.Thebay’srockyintertidalzonenormallyhostsathrivingcommunityofmussels,barnacles,limpets,anemonesandalgae.ButitchangedcompletelyafterPainebanishedthestarfish.Thebarna-clesthattheseastar(Pisasterochraceus)usuallyateadvancedthroughthepredator-freezone,andwerelaterreplacedbymussels.TheseinvadersDYNASTYBobPainefatheredanidea—andanacademicfamily—thatchangedecology.BYEDYONGBobPaine’sacademicfamilytree,drawnbyMarianKohnin1999.286|NATURE|VOL493|17JANUARY2013FEATURENEWS?2013MacmillanPublishersLimited.Allrightsreservedcrowdedoutthealgaeandlimpets,whichfledforlesscompetitivepas-tures.Withinayear,thetotalnumberofspecieshadhalved:adiversetidalwonderlandbecameablackmonocultureofmussels1.Byre-engineeringthecoastlineinthisway1,Painedealtaseriousblowtothedominantviewinecologyofthetime:thatecosystemsarestabledramasiftheyhaveadiversecastofspecies.Instead,heshowedthatindividualspeciessuchasPisasterareprimadonnas,whoseabsencecanwarptheentireproductionintosomethingblanderandunrecognizable.Hedescribedthesecrucialcreatures,whoseinfluencefarexceedstheirabundance,askeystonespecies,afterthecentralstonethatpreventsanarchfromcrumbling.TheirlosscaninitiatewhatPainewouldlatercalltrophiccascades—theriseandfallofconnectedspeciesthroughoutthefoodweb.Thetermsstuck,and‘keystone’wouldgoontobeappliedtospeciesfromseaotterstowolves,greywhalesandspottedbass.Today,ecologystudentstaketheseconceptsforgranted—buttheyshookthefieldwhenPainefirstarticulatedtheminthe1960s.“He’s