Symaptric speciation is the formation of new species in populations that live in the same geographic area, while allopatric speciation occurs when the population is separated by a geographcial area. So, according to this: The difference between the sympatric speciation and the allopatric speciation is that sympatric speciation involves a behavioral barrier, while allopatric speciation involves a physical barrier.
True - An extensive chain of mountains or mountain ranges, especially the principal mountain system of a continent.