SamuwarKimiyya

Zabin yanayi. Material selection. Basic Principles of abu selection

Our Mother yanayi ne sosai hikima. Rauni, kuma ba ya dace da jiki kawai yana da wani damar cigaba da rayuwa. Shin yana yiwuwa a cikin halitta dokokin ba da damar rashin lafiya dabbobi ba da wannan m zuriya? Hakika ba, don haka da cewa duk kwayoyin yi yãƙi, domin rayuwa. A lashe wannan yaki ne da karfi, da tauri, fittest da lafiya. Saboda haka zabin yanayi. Material selection da kuma yadda shi zai la'akari a cikin labarin a more daki-daki.

A ra'ayi na zabin yanayi

Idan ka ba mai definition, zamu iya cewa wannan tsari, wadda take kaiwa zuwa wani karuwa a yawan da ya fi yiwuwa da kuma saba mutane. Rauni da kuma talauci saba kawai ba zai iya gasa. Roba ka'idar juyin halitta ya wadãtu da zabin halitta ', abu selection, a matsayin tushen duk adaptations da kuma ilimi supraspecific Categories.

Zabin halitta ', ko a dauke su a cikin hanyar karbuwa daga kwayoyin da yanayi, amma ba shi ne kadai ne m juyin halitta a cikin yanayi. A lokaci gabatar da Charlz Darvin, wanda da yawa daga cikin ayyukan da kishin nazarin wannan tambaya.

Daga wanda shi ya bi zabin yanayi

Kwayoyin halittu a wani kwayoyin iya maye gurbi, wanda zai iya faruwa ga dalilai daban-daban. A kan aiwatar da zabin yanayi shine Abubakar, fãce wanda ya taimaka da karbuwa daga kwayoyin da yanayi. Popular sau da yawa ake magana a kai a matsayin kai ne bayyanannu zabin yanayi, kamar yadda shi ya bi daga dalilai da dama:

  1. Kowane kwayoyin ne iya samar da zuriya haske yawa fiye da zai iya tsira.
  2. A wata alƙarya, akwai wani kwayoyin bambancin, shi ne albarkatun kasa domin zabin yanayi.
  3. Genetically bambancin kwayoyin sãɓã, a cikinsa ba kawai rayuwa, amma kuma da ikon haifa.

Wadannan dalilai da taimako zuwa ga halittar gasar tsakanin kwayoyin a cikin rayuwa da kuma haifuwa, kuma lalle sũ biyun da wani zama dole yanayin ga juyin halitta yanayi ta hanyar zabin yanayi. A yanayi, don haka ya shirya cewa kwayoyin da m halaye hereditary canja wurin su zuwa zũriyarsu da su, alhãli kuwa mutane ba tare da irin wannan magabaci, da karami da damar wucewa.

selection inji

Gaskiyar cewa ainihin yanayin aza wani inji cewa shi ne kama da wucin gadi selection, da farko ya yi magana Charles Darwin da Alfred Uoles. Su sun natsu da cewa halitta lallai ba ne su shiga cikin kowane irin yanayi - isa ya haifar da wani babban iri-iri na tsuntsaye, daga cikinsu da fittest tsira. selection inji za a iya wakilta kamar haka:

  1. Ana zargin mutane da labari fasali.
  2. Idan alamun akwai amfani, da kwayoyin tsira da barin zuriyarsa.
  3. Zuriyar gãdon amfani halaye da kuma fara canja wurin su zuwa nan gaba.

Duk da cewa zamani kayyade binciken sa nasu sabawa, jigon ka'idar Darwin kasance iri guda. Watakila kawai canje-canje faruwa yawa sauri, amma ba kamar yadda smoothly kamar yadda ya riya, saboda maye gurbi, wanda suke intermittent a yanayi.

A fara abu domin zabin yanayi

Hereditary bambancin ne da kayan wadda take kaiwa zuwa zabin yanayi. All hereditary canje-canje ne sakamakon maye gurbi. Amma ga juyin canji na amfani ne kawai wadanda da shafi jima'i Kwayoyin, domin shi ne, ta hanyar su ne watsa bayanai zuwa gaba tsara.

Mai maye gurbi da recessive hali, watau su iya ba nan da nan ya bayyana a matsayin rinjaye kwayoyin halittu suna mur. Amma da za su tara ko ina daga cikin gene pool na yawan kada tafi, ko da yake, da kuma ba su shafi da suitability kuma ba ya bayyana phenotypically.

Mutational tsari ne m, yawan maye gurbi tara ci gaba, da kuma a daya batu, akwai biyu recessive gene da kuma hali bayyana dole. Abu don nunawa shi ne kwayoyin bambancin, amma irin wannan canje-canje ba ko da yaushe kai ga wani karuwa a da nishaxi, da adaptability. Quite 'yan maye gurbi, a akasin haka, rage ingancin matsayin tsokana daban-daban disturbances a tafiyar matakai na rayuwa.

Amma akwai misalai inda ga alama cutarwa maye gurbi da canje-canje a cikin yanayi na zama da amfani. A houseflies da maye gurbi da ta rage gudun jijiyar. Idan kwayoyin ne homozygous ga wani ba hali, sa'an nan da maye gurbi ne na mutuwa, amma riƙe viability na heterozygotes, ko na baya a fitness lafiya mutane. Amma lokacin da fallasa su da yawan jama'a na kwari shiri jijiya heterozygotes outperform al'ada mutane saboda jinkirin gudun bugun jini raunana da tasiri na guba a jiki.

Nau'in zabin yanayi

A fara abu domin zabin - a kayyade bambancin, amma zai iya bayar da Yunƙurin zuwa wani bugun jini iya canji a wani daban-daban kewayo. Dangane da zabin da irin wannan ne da wadannan:

  • Directed. Yana dabam da talakawan tamanin da halayyar na dogon lokaci. Wadannan sun hada da wani karuwa a jiki size.
  • Damuwa selection ne da nufin a selection na matsananci Manuniya (misali, ma manyan ko, a akasin haka, kananan).
  • Stabizirizuyuschy directed da manifestations na matsananci halayyar dabi'u.

Jima'i - shi ne kuma zabin yanayi. Abu domin zabin da wannan matakin - shi ne wani hali cewa qara Yiwuwar ma'abota ta kara kyawawa da mutum zuwa gaban jima'i. Yana da kyau gani a cikin maza na wasu jinsunan (misali, babbar kaho a barewa, da haske launuka na gashinsa a cikin tsuntsaye).

Nau'i na zabin yanayi

selection form za a iya classified a hanyoyi daban-daban, amma da sharudda ga zabin da abu ne kusan ko da yaushe wannan:

  • A amfani da wannan hali ga mafi mutane.
  • Da bukatar da muhimmancin ga rayuwa hali a wani yanayi.
  • Tasiri a kan ci gaba da alama jinsunan.

Littattafai na wucin gadi selection - shi ne kuma a kayyade bambancin, amma da sharudda ne quite wasu. Akwai alamun da dabino, wadda ake bukata domin mutum, ba jiki, to abin da suka iya duk zama quite cutarwa. Daya zai iya buga misali da zurfin da dutse, wadda ake kira Pectoral Sandpiper. Bã su da wani babban goitre, abin da ya sa su sabon abu da kuma m zuwa ga wani namiji, amma a cikin yanayi na irin wannan mutane za a yi gaba daya m da kuma iya gasa da su takwarorinsu. Suna kawai ba zai iya samun nasu abincin. Sai dai itace cewa zabin da kayan yana da ka'idodi ne sosai daban-daban a cikin halitta da kuma wucin gadi selection.

Dangane da sakamako na selection ga hali canzawa a wata alƙarya ake da wadannan siffofin shi:

  1. Tuki.
  2. Tabbatar da dorewar.
  3. Tearing, ko ansu kafofin tarwatsa.

Akwai bukatar la'akari da kowane selection daidaiku a more daki-daki.

Features tsauri selection

Dalilin wannan zabin ne ko da yaushe canza yanayi ne da wanzuwar jinsin. Mutane da suka yi da sakamakon, akwai alamun cewa karkacewa daga cikin talakawan darajar saboda gaskiyar cewa abu domin zabin yanayi, samar da kwayoyin bambancin, ne mafi daraja. Daga tsara zuwa tsara halayyar shift auku a wani shugabanci, sakamakon da aka kafa irin wannan cewa ya taimaka kwayoyin tsira a cikin sabon yanayi.

A karin misalin mai ci gaba da saka launi a cikin ikonsa ya asu. Ta ke tun da aka kafa ta zauna a cikin kututturan Birch itatuwa, waxanda suke da fari a launi. Haka kuma, da fuka-fuki na malam ne ma fari.

Amma tare da ci gaban tattalin arziki da yanayi da aka gurbata, a cikin iska akwai mai yawa hayaki da toka da ya daidaita a kan bishiya. A sakamakon haka, su launi ya zama nisa daga fari. Daga cikin dukkan malam zurriyar lashe ne daya saboda maye gurbi da wani duhu launi, kamar yadda haske ya quite m ga tsuntsaye da suka sukan ci abinci. Kamar wancan juyin halitta ya hankali canje-canje a cikin shugabanci malam launi.

Bayyanuwar tabbatar da dorewar selection

Ka yi la'akari da tabbatar da dorewar zabin yanayi. Material selection nan - kamar yadda kwayoyin bambancin, amma da aikin da aka riga directed a kan abin da ya faru na sabawa daga na kullum. Za mu iya ba ka wani misali, gama dukan kwayoyin, zai ze, da ƙara haihuwa ne kawai kyau domin kaiwa zuwa wani karuwa a yawan size. Amma a gaskiya shi ne ba. Amfanin ne wani mutum da talakawan haihuwa a matsayin kawo da yawa zuriyarsa ne wuya.

Selection a cikin ni'imar Averages za a iya gani a abubuwa da yawa. Ga misali, da tsuntsaye bakin teku fin so zuwa da fuka-fuki na matsakaici size. A gaban ma short wuya a tashi, kuma idan ta yi tsawo iska za ta tsoma baki tare da jirgin.

Tabbatar da dorewar selection na taimaka wa jari na bambancin a alƙarya. Ko da barga yanayin da jinsunan da ba su kai ga lõkacin fatara daga zabin yanayi da kuma ci gaba a general. Wannan irin Samfur na samar da wani barga aiki na jiki a cikin saba yanayi na yanayi.

ansu kafofin tarwatsa selection

A wannan nau'i na zabin da yanayi na zama su dace da tsakaitãwa na halayyar. A sakamakon haka, akwai dama siffofin zama.

Damuwa selection take kaiwa ga samuwar na polymorphism, kuma zai iya ko zama cikin hanyar samuwar sabon nau'in a yanayi.

Wannan selection sau da yawa ya zo a cikin karfi a lokacin da yawan daukan inhomogeneous mazauninsu. Daban-daban siffofin daidaita da wa daban-daban maharibai da kuma yanayi. Alal misali, wata shuka yi ƙaras-ƙaras yana da siffofi biyu - daya fara Bloom da kuma ba da 'ya'ya a tsakiyar lokacin rani, da kuma na biyu - bayan da hay girbi, watau a cikin watan Agusta.

A muhimmiyar rawa da kuma mummunan selection

Ã'a, shi ne ba da muhimmancin da kuma zabin da siffofin da suke da daban-daban effects.

  1. M selection sakamakon a wani karuwa a yawan kwayoyin ciwon amfani da tsira a wadannan yanayi, cututtuka, da kara rayuwa da jinsunan a matsayin dukan.
  2. Korau, ko kuma ana kiranta da yanke-kashe selection, take kaiwa zuwa ga halaka mutane da cututtuka da cika fuska rage rayuwa da kuma dacewa. Wannan selection daga cikin yawan taimaka wajen cire cutarwa alleles.

selection effects

Mun gano cewa, wani abu selection, dauke da siffar. Amma ya zama dole don bayyana abin da effects bada musamman selection. Tuki leads zuwa fitowan da sabon na'urorin, wannan ya nuna sakamakon da ayyukansa:

  1. Tara. Wannan sakamako ya nuna jari na amfani dabiu daga tsara zuwa tsara. Wannan ya shafi ba kawai ga jiki amma kuma ga mutumin da hukumomin. Alal misali, an karuwa a forebrain, da ci gaba da cerebral bawo - duk wannan misali ne na tuki accumulator selection.
  2. Inganta sakamako ne cewa Littafi amfani da ãyõyinMu, kuma raunana bayyana waɗanda suka yi hasãrar Na'urar muhimmanci.

Da yake jawabi a general game da zabin (material canzawa ne zabin yanayi), za ka iya kiran wani rarraba sakamako da kuma goyon bayan.

Na farko shi ne cewa a mafi sharadi gwargwado, da kwayoyin sau da yawa tsira da kuma samar da zuriya. Inda wadannan yanayi ba hadu dukan bukatun, da rayuwa da kuma haihuwa matsaloli.

Tallafa sakamako ne cewa Na'urar siffofin iya ba za a rage, shi iya ƙara ko zama a wannan matakin.

Abu domin zabin yanayi ne a kayyade bambancin, amma wannan ba shi ne kawai factor cewa taimaka wa ci gaba da rayayyun kwayoyin halitta.

Rawar da zabin yanayi a ci gaba

Ko Charles Darwin ya dabino da zabin yanayi a juyin halitta. Modern roba ka'idar ma ya wadãtu da manyan kayyadewa na ci gaba da zargin adaptations a kwayoyin.

A 19-20 ƙarni a bude na mai hankali yanayin da kwayoyin gado na dabiu ya haddasa abin da wasu masana kimiyya ƙaryatãwa game da muhimmiyar rawar da zabin yanayi. Roba ka'idar juyin halitta, wadda kuma ake kira cigaban Darwiniyanci dogara ne a kan wani gwada yawa bincike na mita na alleles a wata alƙarya an canza a ƙarƙashin rinjayar da wannan zabin yanayi.

Amma kimiyya ba tsaya har yanzu, da kuma binciken 'yan shekarun nan da yawa a cikin fagage daban-daban tabbatar da gazawar na gargajiya roba ka'idar don bayyana duk nuances na juyin rayayyun kwayoyin halitta.

Shawara da kuma shawarwari game da rawar da daban-daban dalilai a tarihi ci gaba da rayuwa duniya da kuma ci gaba a yau. Wata kila wannan shi ne wani tambaya cewa shi ne kusan ba zai yiwu ba a daidai amsar. Amma ba za mu iya ce abu daya: lokacin ne cikakke, a lokacin da dayan ka'idar juyin halitta bukatar bita.

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