Details and sources are here: http://www.seosmarty.com/the-evolution-of-google-authorship-rich-snippets/ Google Authorship Search Snippets have been evolving since 2011 - let's see what was going on!

1. GOOGLE
AUTHORSHIP:
SEARCH
SNIPPETS
By Ann Smarty
@seosmarty
Brand Manager at Internet Marketing Ninjas
Founder of MyBlogGuest.com
Co-founder of ViralContentBuzz.com

2. THE EVOLUTION
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3. June 2011:
FIRST EXPERIMENT WITH SELECTED AUTHORS.
AUTHOR PHOTO IS ON THE RIGHT
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4. October 2011:
THE AUTHOR PHOTO IS MOVED TO THE LEFT;
CIRCLE COUNT, «ADD TO CIRCLES» AND
«COMMENTS ON G+»
ARE ADDED TO THE SEARCH SNIPPET
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5. 2012
«MORE BY AUTHOR NAME» IS ADDED
«COMMENTS ON G+» IS REMOVED.
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6. April 2013:
«MORE BY» IS REMOVED (CLICKING ON THE PHOTO OR
AUTHOR NAME WILL SEND YOU TO THE SIMILAR
RESULTS AS «MORE BY» USED TO).
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7. NOTE: IN LOCAL GOOGLE VERSIONS THERE’S NO WAY
TO GET TO «MORE BY» RESULTS AS BOTH THE PHOTO
AND THE NAME LINK TO AUTHOR’S G+ PROFILE
(The above screenshot is from google.co.uk)
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8. THE TYPES
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9. AUTHORSHIP RESULT + VIDEO RICH SNIPPET
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10. AUTHORSHIP RESULT + REVIEW RICH SNIPPET
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11. AUTHORSHIP RESULT WITH NO CIRCLE INFORMATION
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12. 2 SAME-AUTHOR RESULTS PER ONE SERP: ONLY ONE
GETS A PICTURE!
(THIS HAPPENS VERY SELDOM: MORE OFTEN THAN NOT, IF TWO OF YOUR VERIFIED
RESULTS GET RANKED, ONLY TOP ONE GETS AUTHORSHIP RICH SNIPPET)
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13. AUTHORSHIP RESULT WITH NO PHOTO
(USUALLY THIS HAPPENS WHEN YOUR AUTHORSHIP RESULT HAS
BEEN ONE OF THOSE 10-15% TO BE DROPPED)
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14. AUTHORSHIP RESULTS IN INDEPTH ARTICLES SECTION
(FIRST ANNOUNCED IN AUGUST 2013)
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15. OUTSIDE of
GENERAL SEARCH
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16. AUTHORSHIP RESULTS IN GOOGLE NEWS
(FIRST ANNOUNCED IN NOVEMBER 2011)
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17. AUTHORSHIP RESULTS IN GOOGLE IMAGE RESULTS
(FIRST ANNOUNCED OCTOBER 2013)
INSTEAD OF SHOWING WHO THE IMAGE AUTHOR IS, IT SHOWS WHO THE
AUTHOR OF THE ATTACHED ARTICLE IS (BROKEN!)
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18. EXPERIMENTS
(DEPRECATED)
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19. September 2012:
GOOGLE EXPERIMENTS SHOWING «MORE BY» THE
SAME AUTHOR IF YOU CLICK BACK TO SEARCH
RESULTS
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20. May 2013:
GOOGLE EXPERIMENTS SHOWING RESULTS FOR PDF
FILES
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