http://www.bbc.co.uk/news/world-18702455
Now we know how eggs have mass.
We have previously seen feathers, which were an expected result. The hens are relieved they can now rest for a while, before we move onto experiments in search of the origin of the Hen House. A question which has vexed many and could lead to faster than fox travel, making way for exploration of the cabbage patch in the next field.