Depends on how you are placing the AdSense code on the posts.
If you are placing the code within each post, a manual way would be to create a separate AdSense channel for each author and use that code in the posts.
Another way would be to use the author's name in the url of each post (e.g. "example.com/john-doe/article-title"). That way you can aggregate the reports in AdSense by the url and see the revenue each author's post is bringing in.
I found an example with just GA. Create a custom dimension with the author name. Then display the new segment. Then link your Adsense account to your Adwords account. Then you can see adsense per author. (I believe - have not gotten enough data into GA yet.)
You have to scroll down to the bottom of the page.