A wanzuwar jinsin bambancin - cewa shi ne microevolution

A ra'ayi na juyin halitta a matsayin bunkasuwar dukan abubuwa masu rai a duniya, haduwar rayuwa siffofin da kuma bayyanar da sabon siffofin yau ne yadu amfani a cikin m adabi da kuma a cikin kafofin watsa labarai. Hasashe game da ci gaba da kuma microevolution, da yin amfani da kalma a populist siffofin dilutes da darajar da jawo hankali ga tsari na ainihi. Mene ne micro-juyin halitta a cikin ilmin halitta, da siffar da karshen sakamakon - Waɗannan su ne tambayoyin da aka rufe a wannan labarin.

Juyin halitta a matsayin wata halitta da tsari

Ka'idar juyin halitta ta gano biyu siffofin matukar - Ba'a kuma microevolution - kamar yadda sunadaran da ci gaban rayuwa a duniya. Rarraba da yanaye dangane da size taxonomic raka'a, wadda take kaiwa zuwa wani juyin motsi. Ba'a yakan haifar da samuwar manyan halittun (HALITTAR, iyali, aji, kuma haka a) na dogon lokaci. A sakamakon microevolution - da samuwar sabon nau'in, mafi ƙasƙanci taxonomic naúrar. Saboda haka microevolution ne in ba haka ba ya kira kebantaccen, da samuwar sabon nau'in a tsakiyar asali ta cimma haihuwa warewa da kuma rabuwa a raba taxon.

alamu na ci gaba

Duk da dokokin juyin halitta a matsayin kebantaccen a macrotaxa ratsa wannan labari da wannan dokoki a matsayin na asali naúrar juyin halitta - alƙarya. Mene ne microevolution, sauƙi kwatanta ta da misali na ilimi da alaka, phylogenetically kusa jinsunan a cikin wannan HALITTAR. Alal misali, a cikin Arctic, gida uku a hankali alaka jinsunan like - like Witt, da damisa da kuma Ross sanya hãtimin rufi. Baya daga qananan waje bambance-bambance, da ganima suna quite daban-daban, da suka yi jagoranci ga samuwar hankali related amma jinsuna daban.

iri microevolution

Kebantaccen, wadda take kaiwa zuwa haihuwa neskreschivaemosti kamar yadda na karshe mataki na juyin kadaici kungiyar dake tsakanin jinsunan, yana da sunadaran. Bisa ga irin rufi inji gano wani yawan siffofin. By microevolution sun hada da:

• Geographic kebantaccen.
• Kebantaccen na muhalli rabuwa da jama'a.
• Kebantaccen ta dace haihuwa kadaici (dokopulyatsionnoy da poslekopulyatsionnoy).

Mene ne microevolution Gwargwadon da muhalli?

A wannan yanayin, idan akai la'akari da kadaici inji panmictic (jima'i haifuwa) kungiyoyin na kwayoyin, a lokacin da wani sabon ra'ayi ne kafa a ƙarƙashin rinjayar yanayin ko muhalli dalilai. Kasa kadaici da alƙarya ne dauke da wani factor na wuri mai faɗi canje-canje da kai ga wucin gadi ko cikakken kadaici da alƙarya da wannan nau'in. An misali misali - da samuwar tsibirin jinsunan. Kuma mafi, watakila, da aka sani a cikin wannan mahallin - shi Galapagos bindweed, description da kuma nazari na wanda ya jagoranci Charles Darwin wa ka'idar The Origin of Species. Wani misali na cewa ne microevolution matsayin muhalli kebantaccen an riga an ba - Arctic like. A cikin hali na like muhalli factor shi ne kadaici da abinci wadata. Amma muhalli factor ne ma a hilafa tsakanin kiwo yanayi, daban-daban muhalli jinsi tsakanin jinsunan, da sauransu.

Dokopulyatsionnaya nau'i na kadaici a matsayin wani nau'i na microevolution

A hali na rashin yiwuwar free mararraba na mutane a sakamakon kadaici, guda biyu tare da rashin ilimi da zygote (tayi) na jiki, sai ka ce dokopulyativnoy kadaici. Its siffofin daban-daban:

• Rufi, tasowa saboda yanayin jima'i hali (ethological). Misali - a hankali wurare masu zafi rana, kuma a timbre jinsuna daban bayani dalla-dalla ma'abota tsarkakewa.
• A kadaici lalacewa ta hanyar daban-daban Tsarin copulative da kuma haihuwa gabobin. Misali - jinsuna daban na orchids da wani takamammen tsarin da flower, wanda damar da su zuwa pollinate kawai wani irin hummingbird.

A kadaici lalacewa ta hanyar wani mismatch na gametes. Misalai kawai gwajen halitta hanya, wannan inji shi ne wuya.

Poslekopulyatsionnaya rufi a matsayin wani tsarin ba da kebantaccen

A wannan yanayin yana nufin cewa zygote aka kafa. Mene ne micro-juyin halitta, a cikin wannan yanayin, nuna wadannan siffofin cimma cikakken haihuwa kadaici da alƙarya cikin jinsin:

• Non-viability na zygote a farkon matakai na yanayin halitta na juya.
• Mutuwar ba a haifa ba baby ko matasa mutane su isa haihuwa shekaru.
• A sterility na hybrids.

A nazarin halittu inji wannan nau'i na kadaici ne hadaddun da ake dangantawa da cytological, biochemical da humoral fasali.

Micro-juyin halitta a matsayin wani tsari na cimma cikakken haihuwa kadaici da kungiyoyin cikin wannan jinsin take kaiwa ga samuwar na sabon nau'in kwayoyin wasu fiye da iyaye siffofin. Amma shi ne a ka'idar. Ba kowane kadaici na yawan zai kai ga haihuwa warewa da kuma ba kowace haihuwa kadaici zai kai ga samuwar sabuwar siffofin. Abin da ke a cikin akidarsu juyin halitta - shi ne cewa microevolution farawa da rufi da shi ma ya ƙare.