Final answer:
Geographical isolation can lead to allopatric speciation, resulting in the formation of new species. Different environmental factors and natural selection can cause genetic differences to accumulate in isolated populations.
Step-by-step explanation:
When different members of the same species are geographically isolated for many generations, it is likely that speciation will occur. Speciation is the process by which new species are formed. In the case of geographical isolation, it can lead to allopatric speciation.
In allopatric speciation, a population of organisms becomes geographically separated from the rest of the species. Over many generations, the isolated populations may evolve genetic differences due to different environmental factors and natural selection.
For example, if a population of lizards becomes divided into two groups on different islands, one without predators and the other with a fierce predator, the characteristics of the two lizard populations are likely to differ at the end of 100 years. The lizards on the predator-free island may evolve to have less defensive traits since they are not under constant threat. On the other hand, the lizards on the island with the predator may develop stronger defensive mechanisms to survive.