Do I need to reshape this wide data to effectively use ggplot2?

Question

I have a data.frame that looks like

  Year Crustaceans       Cod       Tuna    Herring Scorpion.fishes
1 1950    58578630   2716706   69690537   87161396             


        

Answer 1

A simple transformation using melt (from the reshape/2 package) would suffice. I would do

library(reshape2)
qplot(Year, value, colour = variable, data = melt(df, 'Year'), geom = 'line')