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On¡¡the¡¡view¡¡here¡¡given¡¡of¡¡the¡¡all¡­important¡¡part¡¡which¡¡selection¡¡by¡¡man¡¡has¡¡played£»¡¡it¡¡becomes¡¡at¡¡once¡¡obvious£»¡¡how¡¡it¡¡is¡¡that¡¡our¡¡domestic¡¡races¡¡show¡¡adaptation¡¡in¡¡their¡¡structure¡¡or¡¡in¡¡their¡¡habits¡¡to¡¡man's¡¡wants¡¡or¡¡fancies¡£¡¡We¡¡can£»¡¡I¡¡think£»¡¡further¡¡understand¡¡the¡¡frequently¡¡abnormal¡¡character¡¡of¡¡our¡¡domestic¡¡races£»¡¡and¡¡likewise¡¡their¡¡differences¡¡being¡¡so¡¡great¡¡in¡¡external¡¡characters¡¡and¡¡relatively¡¡so¡¡slight¡¡in¡¡internal¡¡parts¡¡or¡¡organs¡£¡¡Man¡¡can¡¡hardly¡¡select£»¡¡or¡¡only¡¡with¡¡much¡¡difficulty£»¡¡any¡¡deviation¡¡of¡¡structure¡¡excepting¡¡such¡¡as¡¡is¡¡externally¡¡visible£»¡¡and¡¡indeed¡¡he¡¡rarely¡¡cares¡¡for¡¡what¡¡is¡¡internal¡£¡¡He¡¡can¡¡never¡¡act¡¡by¡¡selection£»¡¡excepting¡¡on¡¡variations¡¡which¡¡are¡¡first¡¡given¡¡to¡¡him¡¡in¡¡some¡¡slight¡¡degree¡¡by¡¡nature¡£¡¡No¡¡man¡¡would¡¡ever¡¡try¡¡to¡¡make¡¡a¡¡fantail£»¡¡till¡¡he¡¡saw¡¡a¡¡pigeon¡¡with¡¡a¡¡tail¡¡developed¡¡in¡¡some¡¡slight¡¡degree¡¡in¡¡an¡¡unusual¡¡manner£»¡¡or¡¡a¡¡pouter¡¡till¡¡he¡¡saw¡¡a¡¡pigeon¡¡with¡¡a¡¡crop¡¡of¡¡somewhat¡¡unusual¡¡size£»¡¡and¡¡the¡¡more¡¡abnormal¡¡or¡¡unusual¡¡any¡¡character¡¡was¡¡when¡¡it¡¡first¡¡appeared£»¡¡the¡¡more¡¡likely¡¡it¡¡would¡¡be¡¡to¡¡catch¡¡his¡¡attention¡£¡¡But¡¡to¡¡use¡¡such¡¡an¡¡expression¡¡as¡¡trying¡¡to¡¡make¡¡a¡¡fantail£»¡¡is£»¡¡I¡¡have¡¡no¡¡doubt£»¡¡in¡¡most¡¡cases£»¡¡utterly¡¡incorrect¡£¡¡The¡¡man¡¡who¡¡first¡¡selected¡¡a¡¡pigeon¡¡with¡¡a¡¡slightly¡¡larger¡¡tail£»¡¡never¡¡dreamed¡¡what¡¡the¡¡descendants¡¡of¡¡that¡¡pigeon¡¡would¡¡become¡¡through¡¡long¡­continued£»¡¡partly¡¡unconscious¡¡and¡¡partly¡¡methodical¡¡selection¡£¡¡Perhaps¡¡the¡¡parent¡¡bird¡¡of¡¡all¡¡fantails¡¡had¡¡only¡¡fourteen¡¡tail¡­feathers¡¡somewhat¡¡expanded£»¡¡like¡¡the¡¡present¡¡Java¡¡fantail£»¡¡or¡¡like¡¡individuals¡¡of¡¡other¡¡and¡¡distinct¡¡breeds£»¡¡in¡¡which¡¡as¡¡many¡¡as¡¡seventeen¡¡tail¡­feathers¡¡have¡¡been¡¡counted¡£¡¡Perhaps¡¡the¡¡first¡¡pouter¡­pigeon¡¡did¡¡not¡¡inflate¡¡its¡¡crop¡¡much¡¡more¡¡than¡¡the¡¡turbit¡¡now¡¡does¡¡the¡¡upper¡¡part¡¡of¡¡its¡¡oesophagus£»¡¡a¡¡habit¡¡which¡¡is¡¡disregarded¡¡by¡¡all¡¡fanciers£»¡¡as¡¡it¡¡is¡¡not¡¡one¡¡of¡¡the¡¡points¡¡of¡¡the¡¡breed¡£¡¡
Nor¡¡let¡¡it¡¡be¡¡thought¡¡that¡¡some¡¡great¡¡deviation¡¡of¡¡structure¡¡would¡¡be¡¡necessary¡¡to¡¡catch¡¡the¡¡fancier's¡¡eye£º¡¡he¡¡perceives¡¡extremely¡¡small¡¡differences£»¡¡and¡¡it¡¡is¡¡in¡¡human¡¡nature¡¡to¡¡value¡¡any¡¡novelty£»¡¡however¡¡slight£»¡¡in¡¡one's¡¡own¡¡possession¡£¡¡Nor¡¡must¡¡the¡¡value¡¡which¡¡would¡¡formerly¡¡be¡¡set¡¡on¡¡any¡¡slight¡¡differences¡¡in¡¡the¡¡individuals¡¡of¡¡the¡¡same¡¡species£»¡¡be¡¡judged¡¡of¡¡by¡¡the¡¡value¡¡which¡¡would¡¡now¡¡be¡¡set¡¡on¡¡them£»¡¡after¡¡several¡¡breeds¡¡have¡¡once¡¡fairly¡¡been¡¡established¡£¡¡Many¡¡slight¡¡differences¡¡might£»¡¡and¡¡indeed¡¡do¡¡now£»¡¡arise¡¡amongst¡¡pigeons£»¡¡which¡¡are¡¡rejected¡¡as¡¡faults¡¡or¡¡deviations¡¡from¡¡the¡¡standard¡¡of¡¡perfection¡¡of¡¡each¡¡breed¡£¡¡The¡¡common¡¡goose¡¡has¡¡not¡¡given¡¡rise¡¡to¡¡any¡¡marked¡¡varieties£»¡¡hence¡¡the¡¡Thoulouse¡¡and¡¡the¡¡common¡¡breed£»¡¡which¡¡differ¡¡only¡¡in¡¡colour£»¡¡that¡¡most¡¡fleeting¡¡of¡¡characters£»¡¡have¡¡lately¡¡been¡¡exhibited¡¡as¡¡distinct¡¡at¡¡our¡¡poultry¡­shows¡£¡¡
I¡¡think¡¡these¡¡views¡¡further¡¡explain¡¡what¡¡has¡¡sometimes¡¡been¡¡noticed¡¡namely¡¡that¡¡we¡¡know¡¡nothing¡¡about¡¡the¡¡origin¡¡or¡¡history¡¡of¡¡any¡¡of¡¡our¡¡domestic¡¡breeds¡£¡¡But£»¡¡in¡¡fact£»¡¡a¡¡breed£»¡¡like¡¡a¡¡dialect¡¡of¡¡a¡¡language£»¡¡can¡¡hardly¡¡be¡¡said¡¡to¡¡have¡¡had¡¡a¡¡definite¡¡origin¡£¡¡A¡¡man¡¡preserves¡¡and¡¡breeds¡¡from¡¡an¡¡individual¡¡with¡¡some¡¡slight¡¡deviation¡¡of¡¡structure£»¡¡or¡¡takes¡¡more¡¡care¡¡than¡¡usual¡¡in¡¡matching¡¡his¡¡best¡¡animals¡¡and¡¡thus¡¡improves¡¡them£»¡¡and¡¡the¡¡improved¡¡individuals¡¡slowly¡¡spread¡¡in¡¡the¡¡immediate¡¡neighbourhood¡£¡¡But¡¡as¡¡yet¡¡they¡¡will¡¡hardly¡¡have¡¡a¡¡distinct¡¡name£»¡¡and¡¡from¡¡being¡¡only¡¡slightly¡¡valued£»¡¡their¡¡history¡¡will¡¡be¡¡disregarded¡£¡¡When¡¡further¡¡improved¡¡by¡¡the¡¡same¡¡slow¡¡and¡¡gradual¡¡process£»¡¡they¡¡will¡¡spread¡¡more¡¡widely£»¡¡and¡¡will¡¡get¡¡recognised¡¡as¡¡something¡¡distinct¡¡and¡¡valuable£»¡¡and¡¡will¡¡then¡¡probably¡¡first¡¡receive¡¡a¡¡provincial¡¡name¡£¡¡In¡¡semi¡­civilised¡¡countries£»¡¡with¡¡little¡¡free¡¡communication£»¡¡the¡¡spreading¡¡and¡¡knowledge¡¡of¡¡any¡¡new¡¡sub¡­breed¡¡will¡¡be¡¡a¡¡slow¡¡process¡£¡¡As¡¡soon¡¡as¡¡the¡¡points¡¡of¡¡value¡¡of¡¡the¡¡new¡¡sub¡­breed¡¡are¡¡once¡¡fully¡¡acknowledged£»¡¡the¡¡principle£»¡¡as¡¡I¡¡have¡¡called¡¡it£»¡¡of¡¡unconscious¡¡selection¡¡will¡¡always¡¡tend£»¡¡perhaps¡¡more¡¡at¡¡one¡¡period¡¡than¡¡at¡¡another£»¡¡as¡¡the¡¡breed¡¡rises¡¡or¡¡falls¡¡in¡¡fashion£»¡¡perhaps¡¡more¡¡in¡¡one¡¡district¡¡than¡¡in¡¡another£»¡¡according¡¡to¡¡the¡¡state¡¡of¡¡civilisation¡¡of¡¡the¡¡inhabitants¡¡slowly¡¡to¡¡add¡¡to¡¡the¡¡characteristic¡¡features¡¡of¡¡the¡¡breed£»¡¡whatever¡¡they¡¡may¡¡be¡£¡¡But¡¡the¡¡chance¡¡will¡¡be¡¡infinitely¡¡small¡¡of¡¡any¡¡record¡¡having¡¡been¡¡preserved¡¡of¡¡such¡¡slow£»¡¡varying£»¡¡and¡¡insensible¡¡changes¡£¡¡
I¡¡must¡¡now¡¡say¡¡a¡¡few¡¡words¡¡on¡¡the¡¡circumstances£»¡¡favourable£»¡¡or¡¡the¡¡reverse£»¡¡to¡¡man's¡¡power¡¡of¡¡selection¡£¡¡A¡¡high¡¡degree¡¡of¡¡variability¡¡is¡¡obviously¡¡favourable£»¡¡as¡¡freely¡¡giving¡¡the¡¡materials¡¡for¡¡selection¡¡to¡¡work¡¡on£»¡¡not¡¡that¡¡mere¡¡individual¡¡differences¡¡are¡¡not¡¡amply¡¡sufficient£»¡¡with¡¡extreme¡¡care£»¡¡to¡¡allow¡¡of¡¡the¡¡accumulation¡¡of¡¡a¡¡large¡¡amount¡¡of¡¡modification¡¡in¡¡almost¡¡any¡¡desired¡¡direction¡£¡¡But¡¡as¡¡variations¡¡manifestly¡¡useful¡¡or¡¡pleasing¡¡to¡¡man¡¡appear¡¡only¡¡occasionally£»¡¡the¡¡chance¡¡of¡¡their¡¡appearance¡¡will¡¡be¡¡much¡¡increased¡¡by¡¡a¡¡large¡¡number¡¡of¡¡individuals¡¡being¡¡kept£»¡¡and¡¡hence¡¡this¡¡comes¡¡to¡¡be¡¡of¡¡the¡¡highest¡¡importance¡¡to¡¡success¡£¡¡On¡¡this¡¡principle¡¡Marshall¡¡has¡¡remarked£»¡¡with¡¡respect¡¡to¡¡the¡¡sheep¡¡of¡¡parts¡¡of¡¡Yorkshire£»¡¡that¡¡'as¡¡they¡¡generally¡¡belong¡¡to¡¡poor¡¡people£»¡¡and¡¡are¡¡mostly¡¡in¡¡small¡¡lots£»¡¡they¡¡never¡¡can¡¡be¡¡improved¡£'¡¡On¡¡the¡¡other¡¡hand£»¡¡nurserymen£»¡¡from¡¡raising¡¡large¡¡stocks¡¡of¡¡the¡¡same¡¡plants£»¡¡are¡¡generally¡¡far¡¡more¡¡successful¡¡than¡¡amateurs¡¡in¡¡getting¡¡new¡¡and¡¡valuable¡¡varieties¡£¡¡The¡¡keeping¡¡of¡¡a¡¡large¡¡number¡¡of¡¡individuals¡¡of¡¡a¡¡species¡¡in¡¡any¡¡country¡¡requires¡¡that¡¡the¡¡species¡¡should¡¡be¡¡placed¡¡under¡¡favourable¡¡conditions¡¡of¡¡life£»¡¡so¡¡as¡¡to¡¡breed¡¡freely¡¡in¡¡that¡¡country¡£¡¡When¡¡the¡¡individuals¡¡of¡¡any¡¡species¡¡are¡¡scanty£»¡¡all¡¡the¡¡individuals£»¡¡whatever¡¡their¡¡quality¡¡may¡¡be£»¡¡will¡¡generally¡¡be¡¡allowed¡¡to¡¡breed£»¡¡and¡¡this¡¡will¡¡effectually¡¡prevent¡¡selectio

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