Anagenez sahifasining manbasini koʻrish

'''Anagenez''' (anagenesis) — o'zaro chatishtiriladigan populyatsiya sifatida mavjud bo'lishda davom etuvchi [[Tur (biologiya)|tur]]ning bosqichma-bosqich [[evolyutsiya]]sidir. Bu jarayon [[kladogenez]]dan (cladogenesis) farq qiladi; kladogenezda shoxlanish yoki bo'linish sodir bo'lib, ikki yoki undan ortiq nasllar va alohida turlarning paydo bo'lishiga olib keladi.<ref>Futuyma, D.J. (2009). Evolution, 2nd Ed. Sunderland, MA: Sinauer Associates</ref> Anagenez har doim ham ajdod turdan yangi turning shakllanishiga olib kelavermaydi.<ref>{{cite journal | last1 = Archibald | first1 = J.D. | year = 1993 | title = The importance of phylogenetic analysis for the assessment of species turnover: a case history of Paleocene mammals in North America | url = https://archive.org/details/sim_paleobiology_winter-1993_19_1/page/n3 | journal = Paleobiology | volume = 19 | issue = 1| pages = 1–27 | doi = 10.1017/S0094837300012288 | jstor = 2400768| bibcode = 1993Pbio...19....1A | s2cid = 86151240 }}</ref> Turli nasllar ajralib, o'zaro chatishtirish to'xtashi natijasida [[tur hosil bo'lishi]] (speciation) yuz berganda, asosiy guruh dastlabki tur sifatida tavsiflanishda davom etishi mumkin. Mazkur guruhning [[qirilib ketish]] (extinction) yoki turlar seleksiyasisiz rivojlanishi anagenez hisoblanadi.<ref>{{cite journal | last1 = Futuyma | first1 = D.J. | s2cid = 83546424 | year = 1987 | title = On the role of species in anagenesis | url = https://archive.org/details/sim_american-naturalist_1987-09_130_3/page/464 | journal = The American Naturalist| volume = 130 | issue = 3| pages = 465–473 | doi = 10.1086/284724 | jstor = 2461899 | bibcode = 1987ANat..130..465F }}</ref>

== Gipotezalar ==

Mavjud gipotezalardan biriga ko'ra, anagenetik evolyutsiyadagi tur hosil bo'lish jarayonida dastlabki populyatsiya soni tez sur'atlar bilan o'sib boradi. So'ngra barqaror muhitda [[mutatsiya]] va [[Genetik rekombinatsiya|rekombinatsiya]] (recombination) natijasida uzoq vaqt davomida [[Genetik o'zgaruvchanlik|genetik xilma-xillik]] to'planadi. [[Tabiiy tanlanish]] (natural selection) yoki [[Genlar dreyfi|genlar dreyfi]] (genetic drift) kabi boshqa omillar [[Genetik material|genetik material]] va fizik belgilarga shu qadar sezilarli ta'sir ko'rsatadiki, natijada tur avvalgisidan farq qiluvchi yangi tur sifatida e'tirof etilishi mumkin.<ref name="Bilsborough">{{cite journal | last1 = Bilsborough | first1 = A | year = 1972 | title = Anagenesis in Hominid Evolution | url = https://archive.org/details/sim_man-uk_1972-09_7_3/page/481 | jstor = 2800923 | journal = Man | volume = 7 | issue = 3| pages = 481–483 }}</ref>

== Rivojlanishi ==

Anagenez uchun taklif etilgan muqobil ta'rif evolyutsion daraxt shoxiga mos ravishda belgilangan taksonlar va bir yoki bir nechta nomlangan [[Takson|taksonlar]] (taxa) o'rtasidagi nasl munosabatlarini o'z ichiga oladi. Taksonlar tur yoki urug' doirasida bo'lishi kerak va ular ehtimoliy ajdodlarni aniqlashga yordam beradi.<ref>{{cite journal | last1 = MacDonald | first1 = T. | last2 = Wiley | first2 = E.O. | year = 2012 | title = Communicating Phylogeny: Evolutionary Tree Diagrams in Museums | journal = Evo Edu Outreach | volume = 5 | page = 14 | doi = 10.1007/s12052-012-0387-0 | doi-access = free | hdl = 1808/9307 | hdl-access = free }}</ref> Evolyutsion kelib chiqish o'rganilganda, ikki xil mexanizm amal qiladi. Birinchi jarayon genetik ma'lumotning o'zgarishi bilan bog'liq. Bu shuni anglatadiki, vaqt o'tishi bilan organizmlarning [[genom]]larida va rivojlanish bosqichida genlarning o'zaro ta'sirida yetarlicha farqlar yuzaga keladi. Shu tariqa anagenez jinsiy va tabiiy tanlanish jarayonlari hamda genlar dreyfining vaqt davomida rivojlanayotgan turga ta'siri sifatida qaralishi mumkin. Ikkinchi jarayon — tur hosil bo'lishi — kladogenez bilan chambarchas bog'liq. Tur hosil bo'lishi bitta aniq ajdod turdan ikki yoki undan ortiq yangi turlarning ajralib chiqishini o'z ichiga oladi. Kladogenezni anagenezga o'xshash gipoteza sifatida ko'rish mumkin, biroq uning mexanizmlariga tur hosil bo'lishi ham qo'shiladi.<ref>{{cite journal | last1 = Wiley | first1 = E.O. | year = 2010 | title = Why Trees Are Important | journal = Evo Edu Outreach | volume = 3 | issue = 4| page = 499 | doi = 10.1007/s12052-010-0279-0 | doi-access = free }}</ref> Tur darajasidagi xilma-xillikka anagenez orqali erishish mumkin.

Anagenez shuni ko'rsatadiki, turda vaqt o'tishi bilan yetarli darajada evolyutsion o'zgarishlar sodir bo'lishi mumkin, natijada keyingi organizmlar alohida tur deb hisoblanadi. Bu holat, ayniqsa, bir turdan ikkinchisiga o'tishni tasdiqlovchi qazilma qoldiqlari bo'lmaganda yaqqol namoyon bo'ladi.<ref name=pmid23378632>{{cite journal |doi=10.1073/pnas.1208302110 |jstor=42583151 |title=Assessing the role of cladogenesis in macroevolution by integrating fossil and molecular evidence |journal=Proceedings of the National Academy of Sciences |volume=110 |issue=8 |pages=2904–9 |year=2013 |last1=Strotz |first1=L. C. |last2=Allen |first2=A. P. |bibcode=2013PNAS..110.2904S |pmc=3581934 |pmid=23378632|doi-access=free }}</ref> Bu kladogenezga — yoki muayyan ma'noda tur hosil bo'lishiga — qarama-qarshi bo'lib, unda populyatsiya ikki yoki undan ortiq [[Reproduktiv izolyatsiya|reproduktiv izolyatsiyalangan]] (reproductively isolated) guruhlarga bo'linadi va ushbu guruhlar alohida turlarga aylanish uchun yetarli farqlarni to'playdi. [[Punktuallizm|Punktuallizm gipotezasi]] (punctuated equilibria hypothesis) anagenezning kamdan-kam uchrashini va evolyutsiya tezligi kladogenezga olib keladigan bo'linishdan so'ng darhol eng yuqori bo'lishini ta'kidlaydi, biroq anagenezni butunlay inkor etmaydi. Anagenez va kladogenezni farqlash qazilma boyliklarini o'rganishda muhim ahamiyatga ega, chunki vaqt va makon jihatidan cheklangan qazilmalar anagenez, bir turning ikkinchisi bilan almashishi (kladogenez) yoki oddiy migratsiya shakllarini ajratishni qiyinlashtiradi.<ref name=pmid23378632/><ref>{{cite journal |doi=10.1017/S0022336000032224 |jstor=1305998 |title=The Oligocene rodent ''Ischyromys'' of the Great Plains: Replacement mistaken for anagenesis |journal=Journal of Paleontology |volume=67 |issue=2 |pages=297–308 |year=2016 |last1=Heaton |first1=Timothy H. |s2cid=131664395 }}</ref>

So'nggi evolyutsion tadqiqotlar morfologik xilma-xillikni va ''[[Australopithecus anamensis]]'' kelib chiqishini tushunish uchun hominin filogenetik daraxtini shakllantirishda anagenez va kladogenez variantlarini ko'rib chiqdi. Mazkur holat qazilma qoldiqlarida anagenezni namoyon qilishi mumkin.<ref name="Kimbel et al.">{{cite journal |doi=10.1016/j.jhevol.2006.02.003 |pmid=16630646 |title=Was ''Australopithecus anamensis'' ancestral to ''A. Afarensis''? A case of anagenesis in the hominin fossil record |journal=Journal of Human Evolution |volume=51 |issue=2 |pages=134–52 |year=2006 |last1=Kimbel |first1=W |last2=Lockwood |first2=C |last3=Ward |first3=C |last4=Leakey |first4=M |last5=Rak |first5=Y |last6=Johanson |first6=D |bibcode=2006JHumE..51..134K }}</ref>

Populyatsiyada yetarli darajada mutatsiyalar sodir bo'lib, ular barqarorlashganda va populyatsiya ajdodidan sezilarli darajada farqlanganda, unga yangi tur nomi berilishi mumkin. Bunday turlar seriyasi umumiy holda evolyutsion nasl deb ataladi.<ref>[[Kaliforniya universiteti (Berkli)]] manbasiga ko'ra, nasl (lineage) — «Uzluksiz nasl-nasab chizig'i; ajdod/nasl munosabatlari bilan bog'langan organizmlar, populyatsiyalar, hujayralar yoki genlar ketma-ketligi». [http://evolution.berkeley.edu/evolibrary/glossary/glossary.php?start=g&end=m Understanding Evolution, Glossary of Terms] {{Webarchive|url=https://web.archive.org/web/20171201131511/https://evolution.berkeley.edu/evolibrary/glossary/glossary.php?start=g&end=m |date=2017-12-01 }}</ref><ref>[[Oksford ingliz tili lug'ati]] biologik naslni «har biri o'zidan oldingisidan rivojlangan deb hisoblangan turlar ketma-ketligi» deb belgilaydi.[https://web.archive.org/web/20070930004858/http://www.askoxford.com/concise_oed/lineage?view=uk OED definition of lineage]</ref> Evolyutsion nasl davomidagi turli turlar [[Xronotur|xronoturlar]] (chronospecies) deb ataladi. Agar xronoturning ajdod populyatsiyasi qirilib ketmasa, bu jarayon kladogenez hisoblanadi va ajdod populyatsiya [[Parafiliya|parafiletik]] tur (paraphyletic species) yoki paratur bo'lib, evolyutsion gradani tashkil etadi.

== Insonlarda ==

Zamonaviy insoniyatning kelib chiqishi borasidagi bahslar tadqiqotchilarni yanada chuqurroq javoblar izlashga undadi. Tadqiqotchilar hozirgi insonlar Afrikadan kelib chiqqanmi yoki anagenez orqali Afro-Evrosiyoda yashagan yagona arxaik turdan rivojlanganmi degan savolga qiziqish bildirishdi.<ref>{{cite journal | last1 = Relethford | first1 = J.H. | year = 2008 | title = Genetic evidence and the modern human origins debate | url = https://archive.org/details/sim_heredity_2008-06_100_6/page/n20 | journal = Heredity | volume = 100 | issue = 6| pages = 555–563 | doi = 10.1038/hdy.2008.14 | pmid=18322457| doi-access = free | bibcode = 2008Hered.100..555R }}</ref> [[Milford H. Wolpoff]] — [[paleoantropolog]] (paleoanthropologist) bo'lib, uning inson qoldiqlari ustidagi izlanishlari [[hominid]]lar (hominin) evolyutsiyasida anagenez gipotezasini o'rgangan.<ref>Wolpoff, M. H. (n.d.). Milford Wolpoff. Retrieved from https://sites.lsa.umich.edu/wolpoff/</ref> Gominidlarda anagenezni o'rganishda M. H. Wolpoff uni «yagona tur gipotezasi» (single-species hypothesis) doirasida tasvirlaydi. Bu gipoteza madaniyatning turga adaptiv tizim sifatida ko'rsatadigan ta'sirini va insonlar yashaydigan sharoitlarni ekologik nisha asosida tushuntirish bilan xarakterlanadi. Madaniyatning adaptiv tizim sifatidagi ta'sirini baholashda olimlar birinchi navbatda zamonaviy ''Homo sapiens''ni ko'rib chiqishlari kerak. Wolpoffning ta'kidlashicha, o'tmishdagi qirilib ketgan ''Hominidae'' oilasining ekologik nishasi nasl chizig'i ichida alohida ajralib turadi.<ref name="Bilsborough" /> Ilk [[Pliootsen]] va kech [[Miotsen]] topilmalarini o'rganish morfologik farqlar davrida anagenez va kladogenezning ahamiyatini aniqlashga yordam beradi. Ushbu topilmalar inson va shampanze shoxlari bir vaqtlar bir-biridan ajralganligini ko'rsatadi. Hominin qoldiqlari 5–7 million yil avvalgi davrga borib taqaladi.<ref name="Kimbel et al." /> Tur darajasidagi xilma-xillikka anagenez orqali erishish mumkin. To'plangan ma'lumotlarga ko'ra, faqat bir yoki ikkita ilk homininlar [[Plio-Pleistotsen]] oralig'iga nisbatan yaqin deb topilgan.<ref name="Kimbel et al." /> Ko'proq tadqiqotlar o'tkazilgach, xususan ''A. anamensis'' va ''A. afarensis'' qoldiqlari o'rganilgach, tadqiqotchilar ushbu ikki hominin turi ajdodlar orqali bog'langanligini isbotlashga muvaffaq bo'lishdi.<ref>{{cite journal | last1 = Gibbons | first1 = A | year = 2002 | title = In search of the first hominids | url = https://archive.org/details/sim_science_2002-02-15_295_5558/page/1214 | journal = Science | volume = 295 | issue = 5558 | pages = 1214–1219 | doi = 10.1126/science.295.5558.1214 | pmid = 11847320 | s2cid = 82758224 }}</ref><ref>{{cite journal | last1 = Leakey | first1 = M.G. | last2 = Feibel | first2 = C.S. | last3 = McDougall | first3 = I. | last4 = Walker | first4 = A. | year = 1995 | title = New four-million-year-old hominid species from Kanapoi and Allia Bay, Kenya | url = https://archive.org/details/sim_nature-uk_1995-08-17_376_6541/page/n56 | journal = Nature | volume = 376 | issue = 6541| pages = 565–571 | doi = 10.1038/376565a0 | pmid=7637803| bibcode = 1995Natur.376..565L | s2cid = 4340999 }}</ref><ref>{{cite journal | last1 = Ward | first1 = C.V. | last2 = Leakey | first2 = M.G. | last3 = Walker | first3 = A. | s2cid = 41320275 | year = 2001 | title = Morphology of ''Australopithecus anamensis'' from Kanapoi and Allia Bay, Kenya | journal = J. Hum. Evol. | volume = 41 | issue = 4| pages = 255–368 | doi = 10.1006/jhev.2001.0507 | pmid=11599925| bibcode = 2001JHumE..41..255W }}</ref><ref>White, T.D., 2002. Earliest hominids. In: Hartwig, W. (Ed.), The Primate Fossil Record. Cambridge University Press, Cambridge, pp. 407e417</ref><ref>Wolpoff, M.H., 1999. Paleoanthropology, second ed. McGraw-Hill.</ref> Biroq, William H. Kimbel va boshqa tadqiqotchilar tomonidan to'plangan ma'lumotlar ilk hominin qoldiqlari tarixida anagenez orqali sodir bo'lgan haqiqiy makroevolyutsion o'zgarishlar kam uchraganligini ko'rsatadi.<ref>Levinton, J., 1988. Genetics, Paleontology and Macroevolution. Cambridge University Press, Cambridge.</ref>

== Filogeniya ==

Dinamik evolyutsion xarita (DEM) — ajdodlar va organizmlar o'rtasidagi munosabatlarni kuzatishning boshqacha usulidir. Filogenetik daraxtlardagi shoxlanish naqshi va tur nasli ajralib, rivojlangandan so'ng shoxning qanchalik o'sishi anagenez va kladogenez bilan bog'liq. Biroq, DEMda nuqtalar ushbu turli turlarning harakatini tasvirlaydi. Anagenez DEM bo'ylab nuqta harakatini kuzatish orqali, kladogenez esa nuqtalarning ajralishi va xarita bo'ylab harakatlanishi orqali kuzatiladi.<ref>{{cite journal | last1 = Stephens | first1 = S | year = 2012 | title = From Tree to Map: Using Cognitive Learning Theory to Suggest Alternative Ways to Visualize Macroevolution | journal = Evo Edu Outreach | volume = 5 | issue = 4| pages = 603–618 | doi = 10.1007/s12052-012-0457-3 | doi-access = free }}</ref>

== Tanqid ==

[[Taksonomiya (biologiya)|Taksonomlar]] o'rtasida farqlar yangi tur tasnifini berish uchun qachon yetarli darajada muhim bo'lishi borasida bahslar mavjud. Anagenezni bosqichma-bosqich evolyutsiya deb ham atash mumkin. Tur hosil bo'lishi va nasl evolyutsiyasini anagenez yoki kladogenez sifatida farqlash munozarali bo'lishi mumkin va ba'zi olimlar bu atamalarning zarurligini shubha ostiga qo'yishadi.<ref>{{cite journal |doi=10.1111/bij.12665 |title=Lineages, splits and divergence challenge whether the terms anagenesis and cladogenesis are necessary |journal=Biological Journal of the Linnean Society |volume=117 |issue=2 |pages=165–76 |year=2016 |last1=Vaux |first1=Felix |last2=Trewick |first2=Steven A. |last3=Morgan-Richards |first3=Mary |doi-access=free }}</ref><ref>{{cite journal |doi=10.1111/bij.12885 |title=Species, lineages, splitting, and divergence: why we still need 'anagenesis' and 'cladogenesis' |journal=Biological Journal of the Linnean Society |volume=120 |issue=2 |pages=474–479 |year=2017 |last1=Allmon |first1=Warren|doi-access=free }}</ref><ref>{{cite journal |doi=10.1111/bij.12872 |title=Speciation through the looking-glass |journal=Biological Journal of the Linnean Society |volume=120 |issue=2 |pages=480–488 |year=2017 |last1=Vaux |first1=Felix |last2=Trewick |first2=Steven A. |last3=Morgan-Richards |first3=Mary |doi-access=free }}</ref>

Fan faylasufi [[Marc Ereshefsky]] parafiletik taksonlar anagenez natijasi ekanligini ta'kidlaydi.{{citation needed|date=April 2015}} Qushlarga olib boradigan nasl kertenkele va timsohlardan sezilarli darajada farqlangan, bu esa evolyutsion taksonomlarga qushlarni sudraluvchilar sifatida guruhlangan kertenkele va timsohlardan alohida tasniflash imkonini berdi.<ref>{{cite book |doi=10.1038/npg.els.0003447 |chapter=Philosophy of Biological Classification |title=Encyclopedia of Life Sciences |year=2001 |last1=Ereshefsky |first1=Marc |isbn=0-470-01617-5 }}</ref>

== Qo'llanilishi ==

[[Ijtimoiy evolyutsiya]]ga (social evolution) kelsak, ijtimoiy anagenez/aromorfoz ijtimoiy tizimlarning murakkabligi, moslashuvchanligi, yaxlitligi va o'zaro bog'liqligini oshiradigan universal yoki keng tarqalgan ijtimoiy innovatsiya sifatida ko'rib chiqilishi taklif qilingan.<ref>{{cite journal |doi=10.1080/02604020902733348 |title=Social Macroevolution: Growth of the World System Integrity and a System of Phase Transitions |journal=World Futures |volume=65 |issue=7 |pages=477–506 |year=2009| url=https://www.academia.edu/35162265|last1=Grinin |first1=Leonid |last2=Korotayev |first2=Andrey |s2cid=144845663 }}</ref><ref>{{cite journal | last1 = Grinin | first1 = L. E. | last2 = Markov | first2 = A. V. | last3 = Korotayev | first3 = A. V. | year = 2009 | title = Aromorphoses in biological and social evolution: Some general rules for Biological and social Forms of macroevolution | url = https://www.academia.edu/37045915 | journal = Social Evolution & History | volume = 8 | issue = 2| pages = 6–50 }}</ref>

{{Portal|Evolyutsion biologiya}}

== Manbalar ==
{{Reflist}}

== Tashqi havolalar ==
* [https://www.mun.ca/biology/scarr/Cladogenesis_Anagenesis_Exintction.htm Nyufaundlend universiteti tomonidan taqdim etilgan anagenez va kladogenezni taqqoslovchi diagramma]



[[Turkum:Evolyutsion biologiya tushunchalari]]
[[Turkum:Evolyutsion biologiya terminologiyasi]]
[[Turkum:Evolyutsiya tezligi]]
[[Turkum:Tur hosil bo'lishi]]