11.   He was overthrown by another rebel faction, but the war evolved along ethnic lines.

12.   He was eventually overthrown by another rebel faction, but the war evolved along ethnic lines.

13.   The dictator was overthrown by another rebel faction and the war evolved along ethnic lines.

14.   After all, small communities normally evolve along quite different paths if they are isolated over tens or hundreds of thousands of years.

15.   Waves of African wanderers helped Man to evolve smoothly along a single path rather than branch out into starkly different genetic lines, it suggests.