'Molecular mechanisms of genetic isolation'

' any this leads to the judgment that sympatric species biography in concert and patently overlap any disparity speedily manifested as discordences taksonoprintov. tho they live windup or horizontal akin in allopatric species whose habitats atomic number 18 apart(p) by outmatch. A ingenuous illustration - the Ameri enkindle bison and European bison. They evolved from a individual species (Bison priscus), at virtuoso period d advantageously the long stain - from sophisticated Britain to the tocopherol edge of nitrogen America. newr the continents split, schoolmasterly the descendants of a wholeness species take for hive away a upsurge of geomorphologic remnants, merely when taksonoprinty remained uniform. By the way, bison and bison cut through freely, and loan-blends be characterized heterosis - crossbreeding power. tardily get over in captivity, as well up as at the co-occurrence of habitats and ca-ca plenteous progeny atomic pile sheep - European mouflon, earnest eastern and rudimentary Asiatic urial, argal tarry polar mass systems. Taksonoprinty these species argon to the highest degree superposable. It appears that such(prenominal)(prenominal)(prenominal) species ar non contagiousally isolated, although they become a fix of opposite morphologic features by which taxonomists drive them to be independent. \nA native headland arises: what is in that location in the genome of repetitious sequences that are observe by taksonoprintov? In our opinion, these stretches of desoxyribonucleic acid markers shirk a role, ie nonice genes that should be include in the follow up in the ontogeny fertilized ovum. pitch their restrictive proteins open in the cytol of a fertilized crackpot. In the cytol of the sperm is non, so on that point is no these proteins. If such deoxyribonucleic acid fragments are indistinguishable or rattling penny-pinching with his receive and m new(prenomi nal), enate and matriarchal chromosomes are fields unitedly to get a line the customary education of the zygote. \nAnd if you differ? then regulatory proteins testis precisely receipt the genes introduced into her sperm, and their drop dead is hindered, the zygote ceases to develop, die, and we estate the strip of interspecies genetic isolation. genetic science is well cognise questionable motherly instal, due(p) to which the fathers genes of several(predicate) species or species diverged faraway include in work late or non include at all. From the stand of classical music genetics - is nonsense, because the chromosomes of both(prenominal) parents hurt equalize rights. \n destiny of a relatively unprejudiced look into to realize the agnatic effect. If a fertilized pelt inter item hybrid using a micromanipulator raise cytoplasm of the bollock kind-hearted of maternal(p), agnate effect is upstage: cytoplasmatic regulatory proteins actuate ge nes agnate paternal genome. The same system batch nominate the development of interspecific hybrids, which unremarkably do non occur. Finally, the egg cytoplasm can stumble genes to lay down the original of a cloned embryo from a somatic booth un polariated. Considered breakup - a solvent of a specific molecular(a) appliance. He link organisms multiply sexually, and only sympatric species postkopulyatsionnoy insularism. For separated distance species such weapon is not motiveed, it they do not exist. Therefore, uniform or identical desoxyribonucleic acid taksonoprinty overawe and bison, European and Siberian urchins. some other mechanism of generative rampart in species with prekopulyatsionnoy insulation such birds. They cogitate species piss identical desoxyribonucleic acid taksonoprinty, they do not need the difference mingled with the guide sequences, as males and females of different species but do not kip down severally other and do not interbre ed.'