I'm slightly new to the world of Mathematica, so I can't assess the difficulty of my request, but anyhow, this is my question:

I have 2 datasets that I want to plot with two y axes, and a reversed x axis.
(as to 'why do you want a reversed x-axis': the time parameter is in thousand years before present, which decreases in value as time moves forward, such that 0 is the present day)

The data is the following:

    area = {{0, 443.387}, {1, 443.387}, {2, 443.387}, {3, 443.387}, {4, 
     443.387}, {5, 444.06}, {6, 445.406}, {7, 446.751}, {8, 447.424}, {9,
     698.385}, {10, 718.57}, {11, 734.044}, {12, 772.395}, {13, 
     822.856}, {14, 878.7}, {15, 5933.58}, {16, 6837.85}, {17, 
     7254.32}, {18, 7362.65}, {19, 7458.86}, {20, 7540.94}, {21, 
     7621.01}}                    ;
    distance = {{0, 10.3807}, {1, 10.3807}, {2, 10.3807}, {3, 10.3807}, {4, 
     10.0923}, {5, 10.0923}, {6, 10.0923}, {7, 10.0923}, {8, 
     10.0923}, {9, 9.69003}, {10, 9.65897}, {11, 9.65897}, {12, 
     9.35579}, {13, 8.94344}, {14, 8.22982}, {15, 7.4932}, {16, 
     6.66484}, {17, 5.21611}, {18, 5.21611}, {19, 4.47083}, {20, 
     3.94395}, {21, 3.72562}}     ;

I made a  YY-plot code using this code: http://mathematica.stackexchange.com/a/647/11219, which produces:

![YY_plot-example][1]

And then reversed the original data using the code as found here: http://mathematica.stackexchange.com/a/5717/11219, which should reverse both the data and the axis ticks.

![enter image description here][2]

As I hope you can see: the data is transformed correctly, the labels on the x-axis are not. So in combining the two codes I found, I broke the Ticks on the x-axis. Is it possible to fix this? Even a manual setting of the labels is fine with me, all my plots have the same data range from 21--0. The current code is:

    TwoAxisListLinePlot[{f_, g_}] := 
     Module[{fgraph, ggraph, frange, grange, fticks, 
       gticks}, {fgraph, ggraph} = 
       MapIndexed[
        ListLinePlot[#, Axes -> True, PlotStyle -> ColorData[1][#2[[1]]], 
          Mesh -> Full,
          Ticks -> ({Transpose[({#[[1]], 
                    Reverse@#[[2]], #[[3]], #[[4]]} &@
                  Transpose[Sort@#[[1, 2, 1]]])], #[[1, 2, 2]]} &@
             AbsoluteOptions[ListLinePlot@#1, Ticks])
          ] &, {f, g}]; {frange, grange} = 
       Last[PlotRange /. AbsoluteOptions[#, PlotRange]] & /@ {fgraph, ggraph};
      fticks = 
       Last[Ticks /. 
          AbsoluteOptions[fgraph, 
           Ticks]] /. _RGBColor | _GrayLevel | _Hue :> ColorData[1][1];
      gticks = (MapAt[Function[r, Rescale[r, grange, frange]], #, {1}] & /@
           Last[Ticks /. 
            AbsoluteOptions[ggraph, 
             Ticks]]) /. _RGBColor | _GrayLevel | _Hue -> ColorData[1][2];
      Show[fgraph, 
       ggraph /. 
        Graphics[graph_, s___] :> 
         Graphics[
          GeometricTransformation[graph, 
           RescalingTransform[{{0, 1}, grange}, {{0, 1}, frange}]], s], 
       Axes -> False, Frame -> True, 
       FrameStyle -> {ColorData[1] /@ {1, 2}, {Automatic, Automatic}}, 
       FrameLabel -> {"Years before present [ka]", "Area [km\.b2]", "", 
         "Isolation [km]"},
       FrameTicks -> {{fticks, gticks}, {Automatic, Automatic}}]]

And then run as

    k1 = Transpose@({Reverse[#[[1]]], #[[2]]} &@Transpose@area);
    k2 = Transpose@({Reverse[#[[1]]], #[[2]]} &@Transpose@distance);
    TwoAxisListLinePlot[{k1, k2}]


  [1]: https://i.sstatic.net/wI5og.png
  [2]: https://i.sstatic.net/4Ddi2.png