[tzury]

same applies on counting human photos on social site altogether (flickr, facebook, tweetpic, etc.) would be far more than 6,819,100,000 (population of the world - http://en.wikipedia.org/wiki/World_population)

[TallGuyShort]

http://en.wikipedia.org/wiki/World_population <- Anyone know the reason for the UN's low and medium estimates having serious downturns in population in the next century? Is it because of lowering child-birth rates, or because of expectations of resources/diseases, etc...?

[showerst]

According to the PDF: http://www.un.org/esa/population/publications/longrange2/Wor... it's virtually all due to changes in fertility.

As countries grow in wealth and life expectancy, the number of children per woman tends to drop off drastically.

[ganley]

It's due to zombie apocalypse. Duh.

[Sukotto]

Keep in mind that every picture on that site is hand-made. The instructions disallow photos of actual giraffes or images created on/by a computer.

How many drawings and human-shaped sculpture are there on those social sites? I doubt there's more than the 6.8 billion you quote from wikipedia.