&2'(!/;'( <0 Ļ ÜìôõŰÂÇÎŗĹ¶ŒÎŋŖ÷997-0052 ÙåŇǉÚßƊÛÑÌġw 246-2
Historical Changes in the Definition of Plants: What Do You Say When Asked, “Is This a Plant?”
Key words: kingdom; plant; plastid; taxonomy.
Takashi Nakada
Institute for Advanced Biosciences, Keio University
246-2 Mizukami, Kakuganji, Tsuruoka, Yamagata 997-0052, Japan I\O,ĕİ¢İǒ&Ó*;>&=&ǍÆ+vŸ,ĕİ&ř =&? 7ƍ*ņøǄÎŲ% >-ǍI\O,ĕİ%7¢İ%7( &ř =7>( I\O,³©đǆï%®öŴ AûǍƸwĕİ:<7¢İ)Ɵ &Ŋ;>$ =Ǎvą%¢İ)²6=@)7 ( 6Ǎĕİ%7¢İ%7( &)(=%,fXmgQ+: (ƿĠAû!$Ƥ¢=ſǄ,' ? ǒſǄ+{),ė(ŞŨů²3>$ $Ǎ+ù ,ƱàĦ~$ %%,ĕİĽ)'+: (Ĺİ²6;>$+ǍźǄ&ſǄAÞ=ƕƒA²6$Ǎ+ÄƨAƞ!$465'( Ɵł(ǄÎ+¿ŎAś mr[ǋCarl von Linné:
Carolus LinnaeusǍ1707-1778ǌ,ǍŷĮİAöƱ=ưİĽǋLapideumǌǍ
öƱ$Ĺ$ =ĕİĽǋVegetabileǌǍöƱ$Ĺ$ $ǍŊƊAû!$ =¢İĽǋAnimaleǌ)Ǆ (Linnaeus 1735)mr[+ǄŞ,ǍƢİ|Ǎưİ:<7ǈŘ(ĕİǍĕİ:<7ǈŘ(¢İǍ$ŊïAû"&`WAƢ!Ǎ&ī%¢İ+{%Ċ7ǈŘ(őÎłîñ)ē$ +ǀ¼ 1 mr[+ĽƐ),3ĕİ+®ö,Łƈ>$ (!6Ǎĕİ,ŊƊAû( ǋ"3<ŊƊ)í$Ƥ¢( ǌ&ī%¢İ;¤>$ +ŧďǍmr[,I\O('+źǄ7Ǎǃż(Ƥ¢A( ĤŪ+: (¢İ7Ǎĕİ)Ǆvą%GG`NeqmǋVolvoxǌ+: (ƿĠſǄ,¢İ)Ǆ> (¼ 1)
 19 zş+{ǀ)(!$ƣ£ƒ«ǂ$=&Ǎƣ£A¨ĈǄŞ+ĖśAńüŋŖ1)Ĺİ,ƹØł)Ǆ>Ǎ+ƹŢ,w;ǁ)ǍĽǍƲǍũǋ ǌ
Ǎńǋ7ǌǍŒǍ×Ǎŕ&(!$= -`W(Homo sapiens),¢İĽ ŵŤ¢İƲ ·ũ ƼƱń `WŒ `W×)Ǆ>=ĕİ,--ĕİĽ(Plantae)&$ù@>$6Ǎ%,ĕİAĕİĽ)Ǆ>=Ĺİ&=T. Nakada - 1Ų$bTMnǋErnst HaeckelǍ1834-1919ǌ,źǄAĕİ+ŞŨ+ēƟ)Ů#ǍĕİĽǋPlantaeǌ)ǄǍ¥ťųĹİ,ſǄ% ? &ƿĠƀ% ? &¦ĹĹİǋProtistaǌ)Ǆ> (Haeckel 1866)bTMn,Ƹwĕİ&ƟŬ(ĕİĽǍ`W&ƟŬ(¢İĽAŞŨƴ)¿# $Ǝ6=vą%Ǎƣ£+Ŕã)í$¥ťųĹİAÆťųĹİ;¤¦ĒĹİ&ňĒĹİ2Ǎ®ö+ċĭ('+Ʀ ƭƇƉ>=: )(=&ǍǄŞ+ƈŅ7ëƇ)(!75# 4-'( bTMnƵǍźǄǍſǄǍ$¦ĒĹİ+ù AÞ!$ǍĹİ+Ǆ,Ħ~>).&3+ĢŉA+dETSHuǋRobert H. WhittakerǍ1920-1980ǌ% =æ,¦ĒĹİ;ňĒĹİ0+ƣ£&Ǎ¥ťųĹİ;ÆťųĹİ0+ƣ£AƭƉǍ¯ĉ)ÆťųĹİ+Ĺò+Ʀ )ŉń dETSHu+ĽƐ%,ǍžſǄA²5¦ĒĹİ,i[lĽǋMoneraǌ)ǍňĒ¥ťųĹİ,¦ĹĹİĽǋProtistaǌ)Ǆ>$ÆťųĹİ,®öAƁ ĕİĽǋPlantaeǌ
Ǎ³©
đǆï+ňźĽǋFungiǌǍþǅđǆï+¢İĽǋAnimaliaǌ)¤> (¼ 2; Whittaker 1969)ĹòÎŲ% =dETSHu,ŞŨƴ:<7Ĺò+Ʀ AƭƉǍĕİĽ8ňźĽ,ć;)ŞŨA¨Ĉ$ (!æ+ĕİĽ),ĳŷ)Æťų£AďūŹĕİǋūſǄ&Ƹwĕİǌ
ǍƅſǄǍŠſǄ+ 3 ŞŨ²3>$ $ǍŞŨƴAƭƉÆ+ǄÎŲ+¨ŁAª=&)(=¼ 2 dETSHu+ĽƐǋſǄAūĐ%ŏǌ  -euJjmRǋLynn Margulis, 1938-ǌ,ĕİĽA:<ǈŘ(Ƹwĕİ)ƶÐǍ¥ŞŨů&$ÐŰǍ ;9=ňĒſǄA¦ĹĹİǋProtista 3, Protoctistaǌ)Ǆ (Margulis1971, 1974)euJjmR):=ěį+ĽƐ%,ĕİĽǍňźĽǍ¢İĽ,ŞŨł):3&6;>Ǎ¦ĹĹİĽ,Ơ)ǍŞŨƴxć(ƺÆ(¦Ĺ¢İ8ſǄǍňź%( źǄǋźǄǌ('A²5: )(!2)¦ĒĹİ&ňĒĹİ,ĒŶ+ċĭ('Ǎťųƫ+ĖƢÇľ(!$ =¦ĒĹİ+{%7žſǄǋQD\^KUmDǌ,ƬţŁĹ¾+®öAƁ Ǎĕİ&$ù@>=&7 !T. Nakada - 2 vƫ+ǄÎŲ,ŞŨł)ƺÆ(¦ĹĹİAƋtăĸ=&AńüǍňĒĹİAĊÇ 18Ľ)Ǆ=Ĕ7> (Leedale 1974)+: (ÆĽƐ+{),ǍĕİĽ&°œ;ĺ ǍƸwĕİAūſǄ&)ūŹĹİĽǋChlorobiotaǍViridiplantae ('ǌ&$ù 7+7! (Jeffrey 1971, Cavalier-Smith 1981) >+ǄŞ) $7ǍňĒĹİ+{%ſǄ8Ƹwĕİ+Ľ)Ǆ>$ $ǍŹţ+ƣ£AƐć=&,%(!85'(1.$ dETSHuƵǍĕİĽ+Ś»Ð3;(!Ƈº&$ǍťųĖƢ+ľ(=ſǄůŹţAû!$ =&ƓƋĢ%(!&&ǍſǄů+ƳǍ = ,­ſǄů&+¦ĹĹİ+Ƴ+ŞŨƴxć!&ý;>=+Ħ~AƋĢ)Ô +,ǍĚĹ&

ķƖ+Łƈ&ǍËŞŨƋĎ+ŁÖ% ! ňĒĹİ+Źţ,Ǎ¦ĒĹİ+žſǄňĒĹİ)ťųĹǋvĚĹǌ7+&ű ;>$ vƫ+ſǄ+ŹţŹţAû!+ňĒĹİ+ťųĹǋĚĹǌ)ļč=&ć;&(<Ǎľ(=ťųĖƢAû!ſǄ:ŹţA
û!$ =&Ɛć%=: )(! ĚĹ):=ƣ£Aűó)>$ǍňĒĹİ+ǄAĖö+HsCmFǑRfR
ǋThomas Cavalier-SmithǍ1942-ǌ% =æ,¦Ĺ¢İ&:ťųĖƢAû"ſǄů+ÆǍ+ňĒĹİ;ŹţAĵèËÏ% =&ű $ĚĹſ,vĚĹĕİǋƸwĕİ7²5ǌ&,Źţ+ƚĨľ(=6ǍĕİĽ;ƷÅǍvĚĹĕİ% =ĪŹſǄǍŠſǄǍūŹĕİAĕİĽ)3&6 (Cavalier-Smith 1998, 2002, 2007) vą%ËŞŨƋĎ+ƣĜ):!$ǍåòÎ%,Ƌ(!ǍňĒĹİ+ŞŨƴć;)(!$ķ½ǍňĒĹİ),Ç 3 "+ŞŨÍ½=&ű ;>$ =v",¢İ&ňźǄǍƆƿĠƀ(';(=çąƿĠǄǋopisthokontsǌǍv",ŻĲĀƜAû!Dhu^8ŜźǄŘA²5Dhu^¢İǄǋamoebozoansǌǍ$Ċç)ſǄ8ƸwĕİǍÆ+¦ĹĹİ;(=^EOrSǄǋbikontsǌ% =^EOrSǄ),DncGluSǄǋAlveolataǐŭĠƀ8ħƿĠſǄ('ǌǍFKRHsCuSǄǋExcavataǐfXmgQ8ė(ƿĠƀǄǌǍmPmDǄǋRhizariaǐŝĲĀƜAû"Dhu^ǍKpllKZGſǄ('ǌǍRWlh\_EnǄ
ǋstramenopilesǐźǄ8á"+ƿĠƀǄǍxŘĠſǄ('ǌǍ]aWſǄǍKmaWſǄǍ$ 3 ŞŨ+vĚĹĕİ²3>=
 ƄĂ+ƪË%ňĒĹİ+ŞŨƋĎƁ@>=&ǍvĚĹĕİ )ƟŬ% =&ËŞŨ;7āû> (Baldauf et al. 2000, Moreira et al. 2000)>):<HsCmFǑRfR+ĕİĽ,ƃ;>ǍĕİǑvĚĹĕİ&951.Ǆª>;>=: )(!'(< 21 zş)<Ǎ:<Æ+ƪðÀ:<Æ+Ĺİ)" $ƋƑ>=: )(=&ǍÇƯ+VuSAĺ ňĒĹİ+ŞŨƋĎŃB)Ɓ@>=: )(!&? $è;>ŞŨĘ%,Ǎë7vĚĹĕİ )ƟŬ&,(;( &ć;)(= ňĒĹİ+ſǄ$^EOrS)²3>=&,Ǎ'+ŞŨƋĎ%7Ä@;( Ǎ^EO

T. Nakada - 3

rS+ƫ+ŞŨƴ,ƋĎ)ĺ =ƪË+Ʃ/ą8ƋĎøģ):!$ľ(=ŧďè;>$= -ƮÝ}ŰǋHisayoshi NozakiǍ1955-ǌ;,^EOrS+{%ŠſǄ,FKRHsCuSǄ)ǍĪŹſǄ8ūŹĕİ,RWlh\_EnǄ8DncGluSǄ):<ƟŬ% =&ƋĎŧďA$ = (Nozaki et al. 2003, 2007, 2009)ǍƠ)vĚĹĕİ )ƟŬ&=ƋĎŧď7ŏ>$ = (Rodríguez-Ezpeleta et al. 2005, Patron et al. 2007, Hackett et al. 2007) (¼ 3)¼ 3 ĴŰ+ĕİĽ&ƛĕİĽvĚĹĕİ,ū%ǍĚĹſ,ƽ%ŏLnua+{)ĚĹſA²5Á®,Ǎúä)ŏ Źţ+ƪË8ƔŞ+ŋŖ;ǍvĚĹĕİ+Źţ,vã<+vĚĹ)ļč
=&ű ;$ =+67ƮÝ;+ŞŨĘě &=&Ǎ^EOrS+ơŐ,Ć)ŹţAû!$ &)(=¡ $ǍÆ+¦Ĺ¢İǋ -DncGluSǄ+ŭĠƀǄ8mPmDǄ+ŝĲĀƜDhu^Ǆ('ǌ8ĚĹſ+Ƨ Ő7vĚĹŹţAû!
$ &)7(=?  +Ɛ)¿# $ǍƮÝ;,vĚĹĕİ&ǍŹţAÈ!$+ĹİA.!=6$ĕİĽ)Ǆ=&AÿĔ$ =æ;,+LnuaA “ƛ” ĕİĽ&µB% $ǍŹţ
AÈ!&î@>=¦Ĺ¢İ(')ƪË+ŀƝ7À´>$ = (Tyler et al. 2006, Maruyama
et al. 2008, 2009, Reyes-Prieto et al. 2008)“ƛ” ĕİĽ),>3%ĕİ&,ű ;>$(!
¦Ĺ¢İ('7²3>$ =Ǎ+¿ĩ,7,8vĚĹŹţAû!$ =&ıê%,( ĕİ&,Õ(&7ŐvĚĹŹţAû!$ Ĺİ% <ǍvĚĹŹţ+ĵè&ƥ§+č)¿# $ =+% =:5'(3 ĕİĽ+ÐŰ,ĉAŦ$ÇÄƗ$¢( Ĺİ&;Ǎ®öAƁ ÆťųĹİ&+ĵè&¥š%Ĭł(ÐŰƣ£ğƹA¨ĈÐŰ)(<Ǎ$ 8vĚĹŹţĝ¬&ŞŨ)¿# ÐŰ)(!$ =ČŊ+Ĺİƈ"!&)Ǎ>ĕİ(+' Aƈ=+,vØƻ(!Ǎ¯ĉ)Ą ÐŰ,ĕİ&Ĺİ0+:<ĥ ĸƋ)¿# $ =&7ƌ = ĊĄ+ĕİĽ+Ś»%,ǍÕ(&7ĪŹſǄǍŠſǄǍūŹĕİ+ 3 ŞŨůvĚĹ):

T. Nakada - 4

!$ŹţAĵèËÏ&ű ;>Ǎ7=&ƆƿĠƀǄ&Dhu^¢İǄAƷ 2&B'+¦ĹĹİ7ĕİ&µ1=+7>( ĕİ+Ś»'3%â=+,Ǎ ç+ŋŖ+ƣÖ)Ê*;>$ = +: )Ǆ&,¥)>,ĕİ% =Ǐ( &¹řAy =7+%,(ǍĹİ+ƣ£tĝ¬)Ò=ĥ ĸƋAƂķ=7+% =7 =Ĺİĕİ' &ƌ Ŀ¸Aû!(;Ǎ+Ĺİ+ƣ£¬)7î AǇ$4$, ? , ǎ'(*(t®öťź ®öAƁ ¦ĒĹİŸAüŠŹťź8ūŹŌǊťźǍūŹƾŌǊťźǍžſǄǋQD
\^KUmDǌ('Ŋ;>=ǍžſǄƬţŁĹ¾®öAƁ ƾƬţŁĹ¾+®
ö,ËęĖ3=%ľ(<ǍžſǄÅ+®öťź,ſǄ)7ĕİ)7²6( (žſǄ,Źţ+ļč)(!tźǄ đǆťų)Ƥ¢ï(®ö7Ɓ@ǍųË%ÃĞ=Ĺİ"$,¦Éł(ĕİ&ű;>ķ½%,źǄ)7ė(ŞŨ²3>=&Ŋ;>$<Ǎvƫ+ſǄ&ƟŬ(źǄ7Í½= @9=I\O+Ƴ,ĳŷ+ňźĽǋFungiǌ)Ǆ>=tſǄ ƬţŁĹ¾®öAƁ Ĺİ+ǍƸwĕİAƷ 7+Ěł)®öŴAÈ!7+

7²6=& =ÆĂ+ŞŨůŊ;>Ǎ¦ĒĹİ+žſǄǋQD\^KUmDǌǍňĒĹİ+ĪŹſǄǍŠſǄǍūŹſǄǋâŰǌǍkuLoYſǄǍKpllKZGſǄǍKmaWſǄǍ]aWſǄǍħƿĠſǄǍxŘĠſǄǋƅſǄǍĶſǄ('ǌ <Ǎ )®öŹţǍƘŽ
İƙǍŹţ8ƿĠ('ťų+éť(ĖƢÇľ(=Ƹwĕİ,ūŹſǄ;ƏĹ&ű ;>= žſǄňĒĹİ)ťųĹ=vĚĹ):<ĪŹſǄǍŠſǄǍūŹſǄǋ&Ƹwĕİǌ+ŹţƏĹǍŹţAû!ňĒſǄ+ňĒĹİ)ťųĹ=ĚĹ):!$kuLoYſǄǍKpllKZGſǄǍKmaWſǄǍ]aWſǄǍħƿĠſǄǍxŘĠſǄ+ŹţĹ3>ĚĹ,Õ(&7 3 ¹ƚ!Ǎěō(¹Ă,@!$ ( Ɵà,vĚĹſ+4Aĕİ&$Ǝ6ǍĚĹſ&,¤=±) ="+%)Baldauf, S.L., Roger, A.J., Wenk-Siefert, I. & Doolittle, W.F. 2000. A kingdom-level phylogeny ofeukaryotes based on combined protein data. Science 290: 972-977.
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