what is a natural selection, genetic drift, and gene flow? would two small, geographically isolated populations in very different environments be likely to evolve in a similar way? explain. Solution natural selection is a process, by which organisam get better adaptation to enviroment for survival and produce more offespring . another defination is process by which the forms of organism in a population that are the best adapted to environment increase in frequency relatively to less adapted forms over a number of generations. this theory was given by Charles Darwin,natural selection is a comosite of all the force that cause differential survival & diffrential reproduction among the genetic variant.natural selection is nonrandom process by which biological traits become more or less common in population, there genetic drift-the random change in allele frequencies caused by sampling error across generations in final population is called genetic drift, drift can be major driving force for changing alleles frequencies in small population , however the key element of genetic drift is that which individuals survive and reproduce is random( unrelated to their phenotype and genotype). drift cause fixation of alleles in population. genetic drift is a random, directionaless process, it act to eliminate genetic variation over a time.drift lead in increase homozygosity for diploid organism and cause increase in inbreeding coefficient, and resulting in facilitate speciation(creating new species) Gene flow-gene flow is transfer of allele and genes from one population to another.through reproduction in same species.gene flow is also non as gene migration, geographically isolated populations in very different environments be likely to evolve in a similar way- speciation is a lineage splitting evolutionary process that produce two or more species, means creation of new and distinct biological species by branching off form ancestral population. occure when gene flow is reduce sufficiently between sister population, and this play critical role in speciation. mode of speciation are often classified as allopatric speciation and sympatric speciation allopatric speciation-geographical isolation between population, and increase genetic divergen by either genetic drift or selection, selection for increase reproduction isolation, and speciation completed. sympatric speciation-does not require geographical isoloation, this reproductive isolation depend on number of factor- like, competition for resources,disruptive selection,sexual selection.