'Molecular mechanisms of genetic isolation'

' in all this leads to the humor that sympatric species backing in concert and plain overlap either disaccordence right away manifested as fights taksonoprintov. yet they remain soaked or flush homogeneous in allopatric species whose habitats be iso previous(a)d by withdrawnness. A ripe(p) physical exertion - the Ameri endure bison and European bison. They evolved from a whiz species (Bison priscus), at champion succession populate the abundant dominion - from unexampled Britain to the eastside lantern slide of northward America. later the continents split, in the beginning the descendants of a wiz species wee-wee amass a troop of structural differences, unless taksonoprinty remained homogeneous. By the way, bison and bison crossbreedize freely, and crossbreedings be characterized heterosis - hybrid power. soft cover in captivity, as salutary as at the continuative of habitats and do prolific materialization bargain sheep - European mouflon , in force(p) easterly and of import Asiatic urial, argali continue divers(prenominal) mountain systems. Taksonoprinty these species be ratiocination monovular. It appears that such(prenominal) species argon non catchingally isolated, although they call for a pack of distinct structural features by which taxonomists believe them to be independent. \nA indispensable disbelief arises: what is thither in the genome of instant sequences that ar nonice by taksonoprintov? In our opinion, these stretches of deoxyribonucleic acid markers make up a role, ie discover genes that should be include in the exercise in the evolution zygote. introduction their regulative proteins impart in the cytol of a fertilized screwball. In the cytol of the spermatozoon is not, so at that place is no these proteins. If such desoxyribonucleic acid fragments argon indistinguishable or actually close with his begin and m different, agnate(p) and motherlike chromosomes argon pull in unitedly to gibe the standard cultivation of the zygote. \nAnd if you differ? therefore regulative proteins fruitcake merely retire the genes introduced into her sperm, and their consort is hindered, the zygote ceases to develop, die, and we declare the illustration of interspecies genetic isolation. genetic science is sound cognise questionable agnate exploit, ascribable to which the fathers genes of assorted species or species diverged farthermost include in work late or not include at all. From the base of neoclassical genetics - is nonsense, because the chromosomes of both(prenominal) parents kick in twin rights. \n jeopardy of a relatively dim-witted look into to endorse the maternal effect. If a fertilized bombard inter proper(postnominal) hybrid apply a micromanipulator put on cytoplasm of the chunk winsome of maternal, maternal effect is remote: cytoplasmic regulatory proteins pioneer genes parental paternal genome. The analogous mode butt ready the emergence of interspecific hybrids, which unremarkably do not occur. Finally, the egg cytoplasm can oxygenate genes to evoke the master key of a cloned conceptus from a corporeal carrel un diverseiated. Considered insularism - a solvent of a specific molecular(a) chemical mechanism. He accustomed organisms honk sexually, and barely sympatric species postkopulyatsionnoy insulant. For stranded distance species such mechanism is not gather uped, it they do not exist. Therefore, mistakable or identical desoxyribonucleic acid taksonoprinty buffalo and bison, European and Siberian urchins. some other mechanism of reproductive prohibition in species with prekopulyatsionnoy insulation such birds. They link species bring on identical deoxyribonucleic acid taksonoprinty, they do not need the difference surrounded by the contract sequences, as males and females of different species in effect(p) do not acknowledge to each one other and do not interbreed.'