Which one of them is correct and why?
According to wikipedia the second figure is correct but I'd like to know why is it so, or why can't be the first one be right?
All I know about allopatric speciation is that it is a process of formation of new species from existing species in the following way-
- A large ancestral population is firstly spatially divided into two subpopulation
- Evolutionary forces act on the subpopulations
- Eventually with large span of time reproductive isolation develops between them and finally lead to new species
According to my concept fig 1 is correct but I find the other diagram all over the internet.