Olimba kusankha: chikhalidwe ndi kufunika mu moyo wa munthu

Monga tikudziwa pa zamoyo, Mwachitsanzo, relict chomera, monga ginkgo, kapena ngati ngati nsomba Crossopterygii monga coelacanth, zilipo pafupifupi palibe kusintha zaka pafupifupi miliyoni. Kodi zimenezi ukugwirizana ndi mtendere wa mitundu mu okhazikika njira kusintha mu chikhalidwe? Yankho la funso limeneli chikuperekedwa kuganizira mfundo "wosasunthika kusankha" - chiphunzitso chakuti lalembedwa ndi wotchuka zamoyo zinachita kusintha II Schmalhausen.

Anati mtundu wa kusankha akhoza anaona zinthu zonse zachilengedwe kwa nthawi yaitali mokwanira. N'chifukwa chake mu malo omwewo, ambiri, zikusonyeza ndi zonse zofunikira kuti izitha kuti munthu wake ndi osiyana penapake kuchokera osinthika izi zidzatha. STABILIZER kusankha zikutsimikiziridwa ndi chiwerengero okwanira zitsanzo. Choncho, pambuyo mkuntho ndi matalala za 136 kakasi mpheta theka akufa anapezeka ku North America, anapulumuka anthu 72 okha. Ena mwa iwo anali mpheta ndi mapiko ambiri, chifukwa chimene iwo anali kupirira kuposa anthu amene anali mapiko a wautali kwambiri kapena chachifupi kwambiri.

Olimba kusankha ndondomeko zimachititsa homogeneity phenotypic wa anthu. Ndi kukhudza wake yaitali pa chilengedwe angakupangitseni kuganiza za wosasinthika nyama kapena anthu. Komabe, ichi ndi zoonekeratu wosasinthika ndi zingawakhudze maonekedwe okha. Pamene dziwe ili jini amaloŵamo kusintha (kusintha kumachitika).

Olimba kusankha khalidwe la munthu. Chitsanzo ndi matenda Down a. Amadziwika kuti matenda otengera chifukwa chisokonezo pa awiriawiri yaing'ono 21-22 DNA. Mu nkhani ya kupatuka iliyonse ya kuchuluka ndiponso mtundu DNA lalikulu, pali chiwonongeko cha mazira ndi umuna. Nthawi zambiri mimba mowiriza imfa ya mazira ndi kuvutika chromosomal pakati.

Olimba kusankha kwa mazana a zikwi za mibadwo, ndi udindo kusamala mitundu ya kusintha kwakukulu ndi kusiya kwa promutirovavschie mawonekedwe. Popanda izo, ndiye kuti sakadaifika utafika kukhazikika mu chirengedwe.

Pamodzi ndi olimba afotokozedwa kale, pali kusankha munthu, umene uli wofunika kwa tikambirane za zomera. Kwenikweni ake ndi kudziwa khalidwe la zomera anasankha mothandizidwa ndi kuganizira munthu wa progenies awo. Mosiyana ndi kusankha misa, sizimayenderana mu mbewu munthu wa zomera amasankhidwa ndi afesedwa payokha mabanja m'madera ena kuti apeze kudzitamandira bwino ana awo. Ndi njira imeneyi mukhoza kusankha pa genotype osati fenotayipi.

Chikomokere kusankha ndi abwino kwambiri kwa munthu, komanso kuchita popanda ntchito pasadakhale yeniyeni. Choncho, Darwin anatsimikizira kuti Mwachitsanzo, pamaso pa chuma osauka ng'ombe ziwiri, nyama izo akapha ndi amene amapereka mkaka wochepa, ndipo nkhuku nyama ndi nkhuku zoipa sanazizolowere. Ndipo mu imodzi, ndipo ngati wachiwiri, mlimi kuti asunge nyama, nachititsa kusankha, musadandaule tokha cholinga kukhala Mitundu latsopano. Ndi mu mawonekedwe penapake wosazindikira Darwin ndipo ikusonyeza chikomokere kusankha.

Mwa kuphunzira za moyo wa anthu a Australia ndi South Africa, asayansi ayamba kukhulupirira kuti chikonzero cha chiweruzo. Chikomokere kusankha kwa nthawi yaitali kuti munthu pa kuthetsa nyama zakutchire. Kuti uwu unali chiphunzitso cha mfundo yofunika kuti ulimi mtundu watsopano wa nyama ndi zomera akhoza analandira kudzera mwa zitsanzo zosankhidwazi. Choncho kuyambira chiphunzitso cha kusankha chikomokere a Darwin "motere" winayo, n'kofunika, chiphunzitso cha kusankha yokumba, amene anakonza mu mawonekedwe a malamulo, kuligonjetsa dongosolo lonse osauka mitundu mbewu yatsopano ndi Mitundu nyama.