Alamu da kuma dokoki na juyin halitta. tsarin juyin halitta

Halittu juyin halitta yakan haifar da wata halitta juyin halitta daga rayayyun kwayoyin halitta, wadda yana tare da canje-canje a cikin kwayoyin abun da ke ciki na daga alƙarya, kazalika da karuwa a cikin Na'urar Properties, bayyanar sabon jinsin da kuma nau'i nau'i na da haihuwa. Dukkan wadannan dalilai canza a kan lokaci duka biyu kunsa da biosphere matsayin dukan.

Ainihin ka'idar

Akwai da dama theories bayanin sunadaran a kan wanda juyin halitta an gina. Mai masana kimiyya suna yanzu aikata zuwa da roba ka'idar juyin halitta (Ste), dangane da ci na yawan itatuwa aure da Darwiniyanci. Roba ka'idar bayyana mahada tsakanin kwayoyin maye gurbi, wato, da kayan juyin halitta da zabin (juyin halitta inji). A tsarin juyin halitta a cikin tsarin na wannan ka'idar ne mita canji tsari na alleles na daban-daban genes a alƙarya jinsunan kan ƙarni da dama.

Alamu da kuma dokoki na ci gaba

A ci gaba ne rashin komowar tsari. Duk wani kwayoyin wanda, da jari na tabbatacce maye gurbi iya daidaita da sabon yanayi, idan dawo wa tsohon matsakaici ya kamata a sake izinin hanyar karbuwa. Haka kuma, babu jinsin ba za a iya cikakken zaunar, Charles Darwin da kansa ya rubuta cewa, ko da idan mazauninsu zai zama iri ɗaya a matsayin kafin, sa'an nan ya samo asali jinsunan ba zai iya dawo da baya jihar. Wancan ne, da dabbobi za su iya daidaita da dawo da tsohon yanayi, amma ba da "haihuwa" hanya.

Wannan za a iya gani a cikin al'amarin tare da dabbobin ruwa. A ciki tsarin da ƙege (tare da kifi Whale) rike ãyõyi dabbobi masu shayarwa reshe. Maye gurbi a gene pool na sabunta tsara, don haka ba a maimaita. Duk da cewa dabbobin ruwa da Whales sun canza da mazauninsu, da kuma biyar-fingered wata gabar jiki - da ƙege, har yanzu suna dabbobi masu shayarwa. Just son dabbobi masu rarrafe samo asali daga halittar dabba mai kafafuwa a wasu mataki, amma ko da baya a tsohon yanayi, ba za su iya bayar da Yunƙurin zuwa halittar dabba mai kafafuwa.

Wani misali na wannan mulki na juyin halitta: wani Evergreen shrub tsintsiya. A ta kara suna located mai haske, da manyan m ganye wanda su ne ainihin modified rassan. A gaskiya ganye ne sikelin-kamar kuma suna located a tsakiyar wadannan "mai tushe." Na sinus flakes farkon spring flower bayyana, daga abin da kara tasowa 'ya'yan itacen. Mahauci samu kawar da ganye a cikin tsarin juyin halitta, a sakamakon ya iya saje da fari, amma sai sake-shigar a cikin ruwa yanayi, amma maimakon wannan ganye aka modified tushe.

inhomogeneity

Sharuddan juyin halitta ce da wannan tsari ne sosai iri-irin da aka ba m da astronomical lokaci. Alal misali, akwai dabbobi da cewa wanzu canzawa daruruwan miliyoyin shekaru. Yana crossopterygian kifi, Tuatara da sablehvost - zaune burbushin. Amma ta faru da cewa kebantaccen kuma bambancin na faruwa sosai hanzari. A karshe 800 shekara dubu a Australia da kuma a cikin Philippines, akwai sabon nau'in hakori, kuma Lake Baikal a lokacin da na karshe 20 shekaru miliyan an wadãtar da 240 jinsunan crabs, wanda ya kasu kashi 34 sabon danginsu. Aukuwa ko canza nau'in ba ya dogara ne a kan lokaci kamar yadda irin wannan, amma da aka ƙaddara da rashin dacewa da kuma yawan al'ummomi. Wannan shi ne, cikin hanzari proliferating jinsunan, da hakan cikin kudi na juyin halitta.

rufaffiyar tsarin

Tafiyar matakai kamar juyin halitta, zabin yanayi da kuma maye gurbi, na iya gudu sosai sauri. Wannan zai faru idan muhalli da yanayi ne m. Duk da haka, a cikin zurfin teku, kogon ruwa, tsibiran da sauran ruwan dare yankuna juyin halitta, zabin yanayi da kuma kebantaccen faruwa sosai a hankali. Wannan ya bayyana cewa da yawa kifi crossopterygian shekaru miliyan kasance canzawa.

Gano da dogaro da kudi na ci gaba da zabin yanayi ne quite sauki kwari. A cikin thirties na karshe karni daga kwari fara amfani da guba da kwayoyi, amma bayan 'yan shekaru akwai jinsunan da suka saba da miyagun ƙwayoyi. Wadannan siffofin sun shagaltar da wani rinjaye matsayi da kuma sauri yada a fadin duniya.

Domin lura da yawa cututtuka ne sau da yawa amfani da karfi maganin rigakafi - penicillin, streptomycin, gramicidin. juyin halitta daga cikin dokokin dauki sakamako: a cikin forties, masana kimiyya sun lura da zargin kwayoyin resistant to wadannan kwayoyi.

regularities

Akwai uku main yankunan juyin halitta, haduwa, da kuma bambanta rarrabuwar parallelism. A lokacin da bambanta rarrabuwar ya kasance mai hankali bambanta rarrabuwar na intraspecific cututtuka da cewa yana yiwuwa kai ga sabon kungiyoyin na mutane. Kamar yadda bambance-bambance a cikin tsari da kuma hanyar da samar da abinci ne mafi zama pronounced, kungiyoyin fara watsa zuwa wasu yankunan. Idan daya yankin da aka yarda, wannan bukatun abinci, a lokacin, a lokacin da samar da abinci zai zama ƙasa, za su yi su bar site da kuma daidaita da wa yanayi daban-daban. Idan a wannan yanki, akwai nau'in da bukatu daban daban, da gasar tsakanin su ne da yawa karami.

A daukan hankali misali na yadda juyin bambanta rarrabuwar daga cikin tsari - shi ne 7 deer jinsunan da alaka da juna: wannan reindeer, barewa, Elk, hange barewa, fallow barewa, Roe barewa da kuma Musk.

Species da wani babban mataki na bambanta rarrabuwar, suna da damar da za su bar mafi zũriyarmu, kuma kasa gasa da juna. Lokacin da ãyõyin bambanta rarrabuwar ne ƙarfafa, da yawan mutane, an raba sub-jinsuna, wanda, a sakamakon zabin yanayi, zai iya yiwuwa ya zama mai raba jinsunan.

al'umma

Haduwa kuma kira akan juyin halitta da tsarin, wanda sa a cikin alaqa jinsunan bayyana kowa siffofin. Wani misali na haduwa ne kama a jiki siffar dabbobin ruwa (dabbobi masu shayarwa), sharks (kifi) da kuma ichthyosaurs (dabbobi masu rarrafe). Wannan shi ne sakamakon da wanzuwar a cikin wannan yanayi da kuma wannan yanayi na rayuwa. Laza da hawainiya Agama ma suna da alaqa, amma sosai irin wannan a zahiri. A fuka-fuki ne ma wani misali na haduwa. Bats da tsuntsãye su zamanto da canza forelegs, amma malam ne wani ginawa-up na jiki. Haduwa ne quite na kowa daga cikin jinsunan bambancin da duniyar tamu.

parallelism

Da kalmar da aka samu daga Girkanci "parallelos", wanda yake nufin "zuwa gaba", da kuma wannan fassarar shi ne mai kyau bayanin ma'anar. Concurrency ne tsari na m saye da irin wannan tsarin fasali tsakanin hankali da alaka da kwayoyin kungiyoyin, abin da ke faruwa saboda gaban fasali, gada daga magabata daya. Wannan irin ci gaba da aka rarraba shi ko'ina a yanayi. Wani misali na shi ne bayyanar fins kamar na'urorin ga mai ruwa-ruwa matsakaici a wadda walruses otariids da phocids kafa a layi daya. Har ila yau daga cikin da yawa winged kwari akwai wani motsi a cikin gaban fuka-fuki elytra. A Crossopterygii akwai alamun halittar dabba mai kafafuwa da kuma dabbobi masu shayarwa-kamar kadangaru, akwai alamun dabbobi masu shayarwa. A gaban parallelism nuna ba kawai da hadin The Origin of Species, amma kuma da wanzuwar irin wannan yanayi.