Question

Consider the following scenario. A large population of lizards occupies an extensive range that is rela-tively uniform ecologically (i.e., in terms of climate and co-occurring species). At a certain point in time, the ancestral population becomes divided down the middle into two similar-sized portions by a barrier that completely prevents the movement of lizards between the descendent populations. Around the same time, a major flood occurs, and a small number of individuals are swept away from the mainland on floating debris and arrive alive on a small offshore island that has no lizards of this species. The habitat on the island is similar to their homeland, but not identical (the climate is slightly different, many main-land species of plants and animals are absent, and a few island species of plants and animals are different from any present on the mainland. Thus, there are now three separate populations. Compare and contrast the expected evolutionary consequences for these populations in the future.

Answer 1

In future speciation will took place. There will be 2 new species formed from the ancestral one. one species will be formed due to division of geographical area by barrier(Allopatric speciation). and one species will be formed due to entering a new place (Parapatric Speciation)

Speciation refers to the origin of new species from pre existing one. It forms the basis of entire course of evolution. The process of splitting a genetically homogenous population into two or more population that undergoes genetic differentiation and eventually reproductive isolation is called speciation.