"Scala also runs on the JVM, so it's fast as opposed to Python."
This is so wide of the mark that I had to comment. The JVM is a fast virtual machine, but that is a poor benchmark. Java and Python run at roughly equitable speeds, but where Python wins out is that it has a much stronger interface to C or Fortran. For hard core number crunching, python wins because you can either call existing scientific or numerical libraries, or use tools like numpy which do the stuff that needs to be fast in C.