Subset data
It is easy to create a subset of a data.frame with the subset command in R.
Symbols lines and colours
Here is some code to quickly access what the colour, line and shape numbers produce.
Lines
Often a model will show a difference between the two levels of a factor. R makes it easy to illustrate the difference graphically.
Extreme heterochiasmy and high rates of sex-reversed recombination result in large yet homomorphic sex chromosomes in the Emei moustache toad
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