The above considerations indicate that the presentday
spatial distribution of red snapper assemblages in
the northern Gulf has a complex history. Glacial advance/
retreat, habitat availability and suitability, and
hydrology are factors that could impact present-day
population structure but might be difficult to detect with
neutral genetic markers if periodic gene flow occurs.
Studies that assess variation in genetic markers affecting
traits under selection would seem a next logical step, as
would precise estimates of rates of exchange among
assemblages.