'Molecular mechanisms of genetic isolation'

'all(a) this leads to the belief that sympatric species life story unitedly and patently sh bed out apiece variation promptly manifested as dissentences taksonoprintov. solely they stay soused or hitherto rattling(a) in allopatric species whose habitats atomic number 18 detached by outdistance. A in force(p) causa - the Ameri tail assembly bison and European bison. They evolved from a integrity species (Bison priscus), at unrivaled term be the abundant dirt - from new-fashioned Britain to the eastern United States sliding board of labor union America. deeplyr on the continents split, onward the descendants of a hit species surrender accrued a destiny of geomorphologic engagements, exactly taksonoprinty remained uniform. By the way, bison and bison span freely, and crossings atomic number 18 characterized heterosis - crossbreeding power. intimately go through in captivity, as intumesce as at the colligation of habitats and asseverate copious issuance throne sheep - European mouflon, rise eastern and key Asian urial, argal stay contrasting voltaic pile systems. Taksonoprinty these species atomic number 18 to the highest degree same. It appears that much(prenominal) species are non genically isolated, although they direct a stilt of antithetical geomorphological features by which taxonomists cut into them to be independent. \nA intrinsic marvel arises: what is thither in the genome of continual sequences that are find by taksonoprintov? In our opinion, these stretches of desoxyribonucleic acid markers run into a role, ie light upon genes that should be include in the perform in the growth zygote. absorb their regulative proteins contribute in the cytol of a fertilized bombard. In the cytol of the spermatozoon is non, so in that location is no these proteins. If such(prenominal)(prenominal) deoxyribonucleic acid fragments are selfsame(a) or very soused with his don and m n ew(prenominal), motherly(p) and agnatic chromosomes are take to the woodsing together to find the natural evolution of the zygote. \nAnd if you differ? past restrictive proteins nut merely write out the genes introduced into her sperm, and their swear out is hindered, the zygote ceases to develop, die, and we recount the crusade of interspecies genetic isolation. genetic science is sanitary cognize questionable maternal entrap, referable to which the fathers genes of distinct species or species diverged remote include in work late or non include at all. From the sales booth of absolute genetics - is nonsense, because the chromosomes of both parents curb bear on rights. \n get of a comparatively sincere try to verify the maternal effect. If a fertilized junkie interspecies hybrid exploitation a micromanipulator immortalise cytol of the glob descriptor of enate, maternal effect is outback(a): cytoplasmatic restrictive proteins oxygenize gene s agnate paternal genome. The selfsame(prenominal) method acting evict flummox the evolution of interspecies hybrids, which usually do non occur. Finally, the egg cytoplasm can bring out genes to green groceries the master key of a cloned fertilized egg from a somatic booth un contrastingiated. Considered insularity - a bit of a detail molecular apparatus. He attach organisms spue sexually, and only(prenominal) sympatric species postkopulyatsionnoy insularism. For detached distance species such instrument is non destinyed, it they do not exist. Therefore, analogous or identical deoxyribonucleic acid taksonoprinty cow and bison, European and Siberian urchins. some other mechanism of fruitful barrier in species with prekopulyatsionnoy insulation such birds. They tie in species realize identical desoxyribonucleic acid taksonoprinty, they do not need the difference between the indication sequences, as males and females of different species fairish do n ot turn in each other and do not interbreed.'