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which pushed his ideas increasingly outof favor。 “eventually；” according to the scientist and historian jeffrey schwartz； “darwin lostvirtually all the support that still remained among the ranks of fellow natural historians andgeologists。”
ironically； considering that darwin called his book on the origin of species； the one thinghe couldn’t explain was how species originated。 darwin’s theory suggested a mechanism forhow a species might bee stronger or better or faster—in a word； fitter—but 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’s 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’t bee dominant insucceeding generations； but in fact would be diluted through blending。 if you pour whiskeyinto a tumbler of water； you don’t 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’s 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—the result ofnoticing some interesting traits of inheritance while pottering about with pea plants in themonastery’s kitchen garden。 in fact； mendel was a trained scientist—he had studied physicsand mathematics at the olmütz philosophical institute and the university of vienna—and 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…timeassistants； he repeatedly bred and crossbred hybrids from thirty thousand pea plants。 it wasdelicate work； requiring them to take the most exacting pains to avoid accidental cross…fertilization and to note every slight variation in the growth and appearance of seeds； pods；leaves； stems； and flowers。 mendel knew what he was doing。
he never used the word gene —it wasn’t coined until 1913； in an english medicaldictionary—though he did invent the terms dominant and recessive。 what he established wasthat every seed contained two “factors” or “elemente；” as he called them—a dominant oneand a recessive one—and these factors； when bined； produced predictable patterns ofinheritance。
the results he converted into precise mathematical formulae。 altogether mendel spenteight years on the experiments； then confirmed his results with similar experiments onflowers； corn； and other plants。 if anything； mendel was too scientific in his approach； forwhen he presented his findings at the february and march meetings of the natural historysociety of brno in 1865； the audience of about forty listened politely but was conspicuouslyunmoved； even though the breeding of plants was a matter of great practical interest to manyof the members。
when mendel’s report was published； he eagerly sent a copy to the great swiss botanistkarl…wilhelm von n？geli； whose support was more or less vital for the theory’s prospects。
unfortunately； n？geli failed to perceive the importance of what mendel had found。 hesuggested that mendel try breeding hawkweed。 mendel obediently did as n？geli suggested；but quickly realized that hawkweed had none of the requisite features for studying heritability。
it was evident to him that n？geli had not read the paper closely； or possibly at all。 frustrated；mendel retired from investigating heritability and spent the rest of his life growingoutstanding vegetables and studying bees； mice； and sunspots； among much else。 eventuallyhe was made abbot。
mendel’s findings weren’t quite as widely ignored as is sometimes suggested。 his studyreceived a glowing entry in the encyclopaedia britannica —then a more leading record of scientific thought than now—and was cited repeatedly in an important paper by the germanwilhelm olbers focke。 indeed； it was because mendel’s ideas never entirely sank below thewaterline of scientific thought that they were so easily recovered when the world was readyfor them。
together； without realizing it； darwin and mendel laid the groundwork for all of lifesciences in the twentieth century。 darwin saw that all living things are connected； thatultimately they “trace their ancestry to a single； mon source；” while mendel’s workprovided the mechanism to explain how that could happen。 the two men could easily havehelped each other。 mendel owned a german edition of the origin of species； which he isknown to have read； so he must have realized the applicability of his work to darwin’s； yet heappears to have made no effort to get in touch。 and darwin for his part is known to havestudied focke’s influential paper with its repeated references to mendel’s work； but didn’tconnect them to his own studies。
the one thing everyone thinks featured in darwin’s argument； that humans are descendedfrom apes； didn’t feature at all except as one passing allusion。 even so； it took no great leap ofimagination to see the implications for human development in darwin’s theories； and itbecame an immediate talking point。