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taking up dubious interests such asspiritualism and the possibility of life existing elsewhere in the universe。 so the theorybecame； essentially by default； darwin鈥檚 alone。
darwin never ceased being tormented by his ideas。 he referred to himself as 鈥渢he devil鈥檚chaplain鈥潯nd said that revealing the theory felt 鈥渓ike confessing a murder。鈥潯part from allelse； he knew it deeply pained his beloved and pious wife。 even so； he set to work at onceexpanding his manuscript into a book…length work。 provisionally he called it an abstract ofan essay on the origin of species and varieties through natural selection 鈥攁 title so tepidand tentative that his publisher； john murray； decided to issue just five hundred copies。 butonce presented with the manuscript； and a slightly more arresting title； murray reconsideredand increased the initial print run to 1；250。
on the origin of species was an immediate mercial success； but rather less of a criticalone。 darwin鈥檚 theory presented two intractable difficulties。 it needed far more time than lordkelvin was willing to concede； and it was scarcely supported by fossil evidence。 where；asked darwin鈥檚 more thoughtful critics； were the transitional forms that his theory so clearlycalled for？ if new species were continuously evolving； then there ought to be lots ofintermediate forms scattered across the fossil record； but there were not。
3in fact； the record asit existed then （and for a long time afterward） showed no life at all right up to the moment ofthe famous cambrian explosion。
3by coincidence； in 1861； at the height of the controversy； just such evidence turned up when workers inbavaria found the bones of an ancient archaeopteryx； a creature halfway between a bird and a dinosaur。 （it hadfeathers； but it also had teeth。） it was an impressive and helpful find； and its significance much debated； but asingle discovery could hardly be considered conclusive。
but now here was darwin； without any evidence； insisting that the earlier seas must havehad abundant life and that we just hadn鈥檛 found it yet because； for whatever reason； it hadn鈥檛been preserved。 it simply could not be otherwise； darwin maintained。 鈥渢he case at presentmust remain inexplicable； and may be truly urged as a valid argument against the views hereentertained；鈥潯e allowed most candidly； but he refused to entertain an alternative possibility。
by way of explanation he speculated鈥攊nventively but incorrectly鈥攖hat perhaps theprecambrian seas had been too clear to lay down sediments and thus had preserved no fossils。
even darwin鈥檚 closest friends were troubled by the blitheness of some of his assertions。
adam sedgwick； who had taught darwin at cambridge and taken him on a geological tour ofwales in 1831； said the book gave him 鈥渕ore pain than pleasure。鈥潯ouis agassiz dismissed itas poor conjecture。 even lyell concluded gloomily： 鈥渄arwin goes too far。鈥�
t。 h。 huxley disliked darwin鈥檚 insistence on huge amounts of geological time because hewas a saltationist； which is to say a believer in the idea that evolutionary changes happen notgradually but suddenly。 saltationists （the word es from the latin for 鈥渓eap鈥潱ouldn鈥檛accept that plicated organs could ever emerge in slow stages。 what good； after all； is one…tenth of a wing or half an eye？ such organs； they thought； only made sense if they appeared ina finished state。
the belief was surprising in as radical a spirit as huxley because it closely recalled a veryconservative religious notion first put forward by the english theologian william paley in1802 and known as argument from design。 paley contended that if you found a pocket watchon the ground； even if you had never seen such a thing before； you would instantly perceivethat it had been made by an intelligent entity。 so it was； he believed； with nature： itsplexity was proof of its design。 the notion was a powerful one in the nineteenth century；and it gave darwin trouble too。 鈥渢he eye to this day gives me a cold shudder；鈥潯eacknowledged in a letter to a friend。 in the origin he conceded that it 鈥渟eems； i freely confess；absurd in the highest possible degree鈥潯hat natural selection could produce such an instrumentin gradual steps。
even so； and to the unending exasperation of his supporters； darwin not only insisted thatall change was gradual； but in nearly every edition of origin he stepped up the amount of timehe supposed necessary to allow evolution to progress； which pushed his ideas increasingly outof favor。 鈥渆ventually；鈥潯ccording to the scientist and historian jeffrey schwartz； 鈥渄arwin lostvirtually all the support that still remained among the ranks of fellow natural historians andgeologists。鈥�
ironically； considering that darwin called his book on the origin of species； the one thinghe couldn鈥檛 explain was how species originated。 darwin鈥檚 theory suggested a mechanism forhow a species might bee stronger or better or faster鈥攊n a word； fitter鈥攂ut gave noindication of how it might throw up a new species。 a scottish engineer； fleeming jenkin；considered the problem and noted an important flaw in darwin鈥檚 argument。 darwin believedthat any beneficial trait that arose in one generation would be passed on to subsequentgenerations； thus strengthening the species。
jenkin pointed out that a favorable trait in one parent wouldn鈥檛 bee dominant insucceeding generations； but in fact would be diluted through blending。 if you pour whiskeyinto a tumbler of water； you don鈥檛 make the whiskey stronger； you make it weaker。 and if youpour that dilute solution into another glass of water； it bees weaker still。 in the same way；any favorable trait introduced by one parent would be successively watered down by subsequent matings until it ceased to be apparent at all。 thus darwin鈥檚 theory was not a recipefor change； but for constancy。 lucky flukes might arise from time to time； but they wouldsoon vanish under the general impulse to bring everything back to a stable mediocrity。 ifnatural selection were to work； some alternative； unconsidered mechanism was required。
unknown to darwin and everyone else； eight hundred miles away in a tranquil corner ofmiddle europe a retiring monk named gregor mendel was ing up with the solution。
mendel was born in 1822 to a humble farming family in a backwater of the austrianempire in what is now the czech republic。 schoolbooks once portrayed him as a simple butobservant provincial monk whose discoveries were largely serendipitous鈥攖he result ofnoticing some interesting traits of inheritance while pottering about with pea plants in themonastery鈥檚 kitchen garden。 in fact； mendel was a trained scientist鈥攈e had studied physicsand mathematics at the olm眉tz philosophical institute and the university of vienna鈥攁nd hebrought scientific discipline to all he did。 moreover； the monastery at brno where he livedfrom 1843 was known as a learned institution。 it had a library of twenty thousand books and atradition of careful scientific investigation。
before embarking on his experiments； mendel spent two years preparing his controlspecimens； seven varieties of pea； to make sure they bred true。 then； helped by two full…timeassista