What forms of isolation do they emit? What are their differences?

There are two forms of isolation: geographical and biological. Geographic (spatial) isolation is the isolation of a certain population from another population of the same species by any difficult to overcome barriers. Geographical isolation impedes the free crossing of individuals of divided populations due to the impossibility of meeting them due to the geographical barrier. Biological isolation is due to biological differences between individuals in populations. Depending on the nature of the differences, four types of biological isolation are distinguished: environmental, ethological, morphophysiological and genetic. Ecological isolation is caused by a shift in reproductive periods (flowering, nesting, mating, spawning periods) or different breeding sites, which impedes the free crossing of individuals of populations. Ethological isolation is due to the behavior of individuals in the mating season. Insignificant at first glance differences in the rituals of courtship during the exchange of visual, sound, chemical signals can lead to the termination of this ritual and restrict mating. Morphophysiological isolation is due to differences in the size of individuals or in the structure of male copulative organs. Genetic isolation is due to large chromosomal and genomic rearrangements that cause differences in the number, shape and composition of chromosomes. It does not prevent the meeting of the sexes and fertilization. But at the same time, it excludes the exchange of genetic information between populations due to the death of zygotes after fertilization.