Pivot table for data already arranged in columns

[birdonawire]

HI I have a spreadsheet of ecological data arranged as plots = rows, species names= columns, abundance = filled cells
I have two replicates for each plot in each years.

Plot 1 Replicate 1: Abn Species 1 Abn Species 2 Abn Sp 3.... sp55..
Plot 1 Replicate 2: Abn Species 1 Abn Species 2 Abn Sp 3.... etc

Plot 2 Replicate 1: Abn Species 1 Abn Species 2 Abn Sp 3.... etc
Plot 2 Replicate 2: Abn Species 1 Abn Species 2 Abn Sp 3.... etc
etc etc

I want to create a summary for each plot by totalling the abundance of each species across the two replicates.
Plot 1: Total abn sp1 Total abn sp 2.... etc

I want the summary to still be plots as rows and species as columns, just summing the two replicates.
I want to then do a second summary using an average or a max value instead of sum...
I tried to design a pivot table but it only allows me to use the species names as data and do a count or an average, but not to keep them as columns..
Is there a way around this? Perhaps I need a different kind of summary tool not a pivot? (I am using Mac Office 2008)

Thanks
birdonawire

[Pepe Le Mokko]

Attach a sample workbook. Make sure there is just enough data to demonstrate your need. Include a BEFORE sheet and an AFTER sheet in the workbook if needed to show the process you're trying to complete or automate. Make sure your desired results are shown, mock them up manually if necessary.

Remember to desensitize the data.

Click on GO ADVANCED and use the paperclip icon to open the upload window.

View Pic

[birdonawire]

Example Data Birdt.xlsx
Please find my attached example data.
Basically I am trying to add every 2 rows together.. but I would like to know the process if it was every 5 rows or 200 rows.. etc..
Thanks for your help!