dat = <|0 -> <|2007 -> 7, 2008 -> 8, 2009 -> 9, 2010 -> 10|>,
        1 -> <|2007 -> 5, 2008 -> 6, 2009 -> 7, 2010 -> 8|>|>;

BarChart[dat,
 ChartLabels -> {Automatic, None},
 ChartLayout -> "Stacked",
 ChartLegends -> Automatic,
 ColorFunction -> ColorData["DeepSeaColors"]]

Unprotect[ColorData];
ColorData["x"] = ColorData[{"DeepSeaColors", "Reverse"}];

BarChart[dat, ChartLabels -> {Automatic, None},
 ChartLayout -> "Stacked", ChartLegends -> Automatic,
 ChartStyle -> "x"]

colors = ColorData[{"DeepSeaColors", "Reverse"}] /@ Subdivide[3];
BarChart[dat, ChartLabels -> {Automatic, None},
 ChartLayout -> "Stacked", ChartLegends -> Automatic,
 ChartStyle -> colors]

Legended[

 PieChart[{mix, males, females},
  ColorFunction -> (Switch[#, mix, LightGreen, males, LightBlue,
      females, LightPink] &),
  ColorFunctionScaling -> False
  (*,ChartLegends[Rule]{"mixed gender","male gender",
  "female gender"} BUG*)
  ]
 ,
 [{LightGreen, LightBlue, LightPink},
  {"Mix", "Male", "Female"}
  ]
 ]