Array.Sort is changing unspecified arrays in unity

I am trying to sort an array, and a list of indices, but I want the original array to stay the same.

When I use the Array.Sort() function, it not only sorts the specified arrays, but also the fitnessVals array (see code below). Does anyone know why this is, and what I can do to stop it from happening?

My code:

        tempFitnessVals = new float[numberOfItems];
        tempFitnessVals = fitnessVals;
        int[] indexes = new int[tempFitnessVals.Length];
        for (int i = 0; i < indexes.Length; i++)
        {
            indexes[i] = i;
        }
        Array.Sort(tempFitnessVals, indexes);
        Array.Reverse(tempFitnessVals);
        Array.Reverse(indexes);

>Solution :

The following code makes a reference and causes the issue you are facing:

tempFitnessVals = fitnessVals;

You need to replace this line with Array.Copy:

...
Array.Copy(fitnessVals, tempFitnessVals, numberOfItems);
...