Scrambled Egg video, tell some of the story.
http://www.cornucopia.org/2010/10/video-scrambled-eggs/
Anecdotally, I recently compared some of our farmers market eggs with eggs from our backyard free ranging birds. Actually, a number of us who have small backyard flocks in the city. What did we find? Our yolks are richer and darker. The more chickens the farmer has, the lighter yellow the yolks (unless he has LOTS of pasture for them to free-range). And even when the farmer tosses in weeds and greens for the hens, their yolks are still lighter than ours. Seems like the hens really need to eat the extra proteins and fats from insects.
http://www.cornucopia.org/2010/10/video-scrambled-eggs/
Anecdotally, I recently compared some of our farmers market eggs with eggs from our backyard free ranging birds. Actually, a number of us who have small backyard flocks in the city. What did we find? Our yolks are richer and darker. The more chickens the farmer has, the lighter yellow the yolks (unless he has LOTS of pasture for them to free-range). And even when the farmer tosses in weeds and greens for the hens, their yolks are still lighter than ours. Seems like the hens really need to eat the extra proteins and fats from insects.