[R] Plot ticks and tick labels: thickness, colour?

[Dirk Eddelbuettel]

I am displaying several series in one plot, and would like to make
them distinct without having to employ a legend. 

I managed to color tickmarks, but have been unsuccessful with either one of 

a) making tickmarks thicker (without increasing the axis at the same time).
   From reading ?axis:
       lty, lwd: line type, width for the axis line and the tick marks.
   in would appear that I cannot obtain the one _without_ the other; or
   
b) displaying the tick label in a different colour. Again, ?axis reads
     col: color for the axis line and the tick marks. [..]
   indicates that I can only set the tick mark, not the annotation.
   
Any ideas or suggestions?

Thanks in advance,  Dirk

-- 
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