No indication of genetic difference was demonstrated in the
two populations of C. temensis, an indication of elevated genetic
flux. ( ) (Tab. 3b).
The results of AMOVA also show this pattern. In the populations of
C. orinocensis, 37,26% of the genetic variation occurred between
the two populations (Fst=0,372; P=0). While in C. temensis, the
variation between the two populations was –0,97% (Fst=-0,0096; P=0.7575).
Fst and AMOVA indicate population fragmentation in C. orinocensis.
These results demonstrate that a distance of ~100 Km between tributaries
of the Rio Negro can function as a barrier to the dispersion of some species
of fish as seen in C. orinocensis, but not in others as in C.
temensis. Species of peacock bass , for example, can exhibit different
patterns of migration, reflectining different life strategies. |
|
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