Qonunhoi asosii evolyutsiyai biologi

Hususiyathoi morfofiziologii organizmhoi zindaro du omili ekologi muayyan mekunad: 1 – talaboti fiziologi; 2 – sharoiti muhiti zist.

Ba hama gunogunshaklii khususiyathoi sokht va mutobiqati juzii organizmho ba muhiti beruna nigoh nakarda, chand qonuniyati umumii ravandi evolyutsioniro qayd kardan mumkin ast.

Qonunkhoi ravandi evolyutsionI

Az sababi ba muddati tuloni davom kardani ravandhoi evolyutsioni mushohida va dar sharoiti tajribavi omukhtani qonuniyathoi umumii ravandi evolyutsioni khele murakkab ast. Ammo fahmidan va tavsif namudani onho muhim meboshad.

Hushbakhtona, dalelhoi sistematika, paleontologiya, anato- miyai qiyosi va digar ilmhoi biologi imkoniyat medihand, ki bo dilpurii kalon ravandi evolyutsioniro dar kategoriyahoi az namud bolo barqaror kunem. Tagyiryobii organizmhoi zindaro ba se shakl judo kardan mumkin ast: divergensiya, konvergensiya va pa- rallelizm.

Divergensiya. Paydo shudani shaklhoi nav hamesha ba mutobiqat ba sharoiti mahalli zist aloqamand ast. Masalan, sinfi shirkhuron va hasharot az otryadhoi (qatorhoi) ziyod iborat ast. Namoyandagoni in qatorho az jihati tarkibi gizo va joyi zist az yakdigar tafovut dorand. Qarib har yak otryad ba zerotryad va oila judo meshavad. Onho na faqat az jihati morfofiziologi, balki bo khususiyathoi ekologi niz farq mekunand. Namudho va zothoi har yak oila niz bo tarzi hayot va tarkibi gizo farq mekunand. CHi tavre ki CH. Darvin nishon dodaast, dar asosi tamomi ravandi evolyutsioni divergensiya meistad.

Durshavii alomathoro na faqat dar namudho, balki dar avlodho, oilaho va qatorho niz didan mumkin ast. Divergensiya dar kadom miqyose boshad, natijai tasiri intikhobi tabii dar shakli intikhobi guruhi meboshad. (Namudho, avlodho, oilaho va g.-ho, yo nigoh doshta meshavand, yo nest meshavand. ). Asosi intikhobi guruhi niz intikhobi fardii dokhili populyatsiya meboshad.

Favti namud az hisobi fardhoi alohida ba amal meoyad. Hususiyathoi morfologii organizmho, ki dar ravandi divergensiya paydo shudaand, dar genofondi shaklhoi qarobatdoshta asosi yagonagii onho meboshand. Masalan, poyhoi hamai shirkhuron, garchande az yakdigar tafovut doshta boshand ham, sokhti naqshi yagona dorand. Az hamin sabab, uzvhoe, ki az jihati sokht bo ham muvofiqandu paydoishashon yagona ast, vale vazifahoi gunogunro ijro mekunand, uzvhoi gomologi nomida meshavand. Dar rustaniho khorhoi nastaran, kaktus, dulona va g.-ho uzvhoi gomologi buda, hamai onho shakli tagyiryoftai barg meboshand. Lundai kartoshka, reshapoyai livondar niz uzvhoi gomologiand.

Konvergensiya.

Rasmi 4.6.

Agama.

Vobasta ba muhiti zist ba buqalamun monand ast.

Konvergensiya to andozae baraksi divergensiya meboshad. Agar hayvonoti az jihati sistematiki kheshutabor nabuda dar sharoiti yakkhela zindagi kunand, uzvhoi onho vazifahoi monandro ijro karda, dar onho uzvhoi ba yakdigar monand paydo meshavand. In hodisaro konvergensiya menomand. Masalan, buqalamun va agama harchand bo yakdigar kheshutabor nestand, vale dar navdai darakht zindagi karda, zohiran ba hamdigar khele monand meboshand (rasmhoi 4.3 va 4.6).

 

Rasmi 4.7. Konvergensiya.

Monandii shakli tan va bol dar hayvonoti tezshinokunandae, ki harobat nadorand:

A – nahang, B – ikhtiozavr, V, G – romuzho (Delfinuo)

Dar hayvonoti muhrador dastu poyhoi khazandahoi bahry va shirkhuron monandii konvergenti dorand (rasmi 4.7). Tarzi zindagii yakkhelai shirkhuroni khaltador va hamrohakdor ba on ovarda rasond, ki novobasta az hamdigar sokhtashon monand shudaast. Kurmushi avrupoi va sanjobi parron ba ham monand meboshand. Gurgi khaltador ba darrandai haqiqi monand ast. Ammo on chi, ki dar ravandi duru darozi tarikhi tashkil yoftaast, ba konvergensiya duchor nameshavad.

Monandii alomatho asosan ba uzvhoe mansub ast, ki bevosita ba sharoiti muhiti yakkhela robita dorand. Dar organizmhoi muhiti faoliyatashon fazobuda bol paydo shudaast (rasmi 4.8). Ammo boli paranda va boli kurshabparak shakli tagyiryoftai poyhoi pesh buda, boli shapalak az hisobi gurrihoi pahlui tan paydo shudaast.

Uzvhoe, ki vazifai yakkhelaro ijro karda, sokht va paydoishi gunogun dorand, uzvhoi shabeh (analogi) nomida meshavand. Masalan, galsamai kharchang va mohi, poyhoi kurmush va gusolasarak, boli shapalak va paranda misolhoi uzvhoi shabeh meboshand. Uzvhoi konvergenti ba guruhhoi az ham durbugumpoyho va muhradoron – imkon dodaast, ki dar khushki zindagi kunand.

Rasmi 4.8. Konvergensiya. Inkishofi mutobiqat baroi bol naafshonda parvoz kardan dar muhradoron: A – mohii parron,

B – kurboqqai parron,

V – agamai parron, G – sanjobi parron.

Dar vaqti ba hayot dar khushki guzashtan dar bugumpoyho va sutunmuhradoron mutobiqate inkishof yoftaast, ki obi organizmro az bukhorshavi nigoh medorad. Masalan, ruypushi gafs, ki obro bukhor shudan nameguzorad. Bisyor hayvonoti obi boshand, mahsuli nolozimi nitrogendorro dar shakli ammiak hamrohi ob khorij mekunand. Dar hayvonoti khushkigard boshad, nitrogen dar shakli durdai peshob khorij meshavad va in imkon medihad, ki obi organizm kamtar bukhor shavad.

Hamin tariq, dar ravandi evolyutsiya mukammalii fiziologii organizmhoi qarobatnadoshta bo rohhoi monand dar zaminai sokhtori gayrigomologi ba amal meoyad. Hamai in dar guruhhoi hamtabor nabuda, natijai tasiri intikhobi tabii meboshad.

Parallelizm. Hamin tavr, Divergensiya tashkilyobii farqiyat dar uzvhoi gomologi, konvergensiya boshad, paydoishi monandi dar uzvho yo guruhhoi hamtabornabuda ast. Parallelizm konvergensiya

Rasmi 4.9. Monandii konvergentii sokhti badan dar shirkhuroni qarobatnadoshtai beshazorkhoi

Afriqo (az chap) va Amrikoi Janubi:

A – bahmuti reza, B – khuki obi, V – gavaznaki afriqoi,

G – paka, D – gavazni reza, E – aguti, J – gizoli khokistarrang, Z – mazama, I – pangolin, K – zirehpushi azim

dar asosi uzvhoi gomologi meboshad, yane parallelizm baroi guruhhoi organizmhoi az jihati genetiki khesh khos ast. Masalan, monandii sokhti tani nahang, ikhtiozavr (khazandai murdarafta) va romuz (rasmi 4.7). Tiri skeleti in hayvonot dar asosi janini gomologii sutunmuhra inkishof yoftaast.

Inchunin hodisai evolyutsionie malum ast, ki monandii organizmho dar zaminai guruhhoi qablan qarobatnadoshta paydo shudaast. Masalan, monandii umumii shirkhuroni qarobatnadoshtai jangalhoi tropikie, ki dar qitahoi mukhtalifi kurai Zamin dar sharoiti iqlimi nazdik zindagi mekunand, malum ast (rasmi 4.9).

Rudimentho (azoi boqi) va atavizm

Rudiment va atavizm zohirshavii du hodisai nazdiki evolyutsioni buda, mahdud yo purra nest shudani vazifai yagon uzv yo sokhtor meboshad. Masalan, dar hayvonoti zerizamini inkishof nayoftani chashm misoli rudiment meboshad. In hodisa natijai az inkishof bozmondani tashkilyobii chashm dar davrahoi avvali taraqqiyoti janin meboshad. Sababi asosii rudiment shudan, ehtimol, gum kardani vazifai ijromekardagi boshad.

Rudiment shudani alomat dar bisyor mavrid natijai tagyirot dar tanzimi genhoi muayyan ast, na dar gum shudani onho. Dar hamai hayvonoti khoki dar davrahoi avvali inkishofi janin misli mohiho kamoni galsama mavjud ast, harchand onho dar hayvonoti kalon yagon vazifaro ijro namekunand.

Atavizm dar organizmho paydo shudani alomathoest, ki na ba kheshoni nazdik, balki ba kheshoni khele dur taalluq dorand. Masalan, paydo shudani 3 panja dar asphoi hozira, gadudi ziyodatii shir, dum, muy dar tamomi badani inson va g. misolhoi atavizm meboshand.

Atavizm daleli on ast, ki dar guzashtagoni duri organizmho, az jumla inson, hamin alomatho vujud doshtaand. YAke az sababhoi paydoishi atavizm nest shudani tasiri sistemai digari genetiki ba genest, ki inkishofi alomatro muayyan mekunad. Hususiyati genotipi organizm, tasiri sharoit ba janin va muhiti beruna, ehtimol, ba paydoishi atavizm ovarda rasonad.