How could groups of fish all swimming together in Lake Victoria ever be isolated enough to produce 300 species?

In other words, the group is reproductively isolated from other groups.

These groups branched off early in human history and have remained relatively genetically isolated since then.

This led him to suggest that the two groups had previously been isolated, but were probably hybridising following secondary contact.

But he and other said the group has apparently become much more isolated in recent years.

Some species or groups of species have been isolated for a long time, while others could stay in close contact.

Classically when a group of people are isolated, they become disoriented and confused.

Genetic data suggests that, although the two groups are isolated from each other, they are both the same species.

Each group was fearfully isolated from its neighbors, and all of them kept their weapons close at hand.

This group has been relatively isolated from the rest of Mexico, with little modernization or formal education.