thank you for this. I didn't realize that even a range was an object. I know, I know, "everything" in Ruby is, but I'm still coming to terms with that. :)

You could do this without the extra variables. you don't need to assign anything to variables in this one. just do the concatenation right in the array creation. Since you aren't modifying the chromosome strings, you don't need the intermediary.

It would be more "Ruby-esque" to not assign them to variables. There is no need for the assignment, so just put the concatentation right in the array creation.