Nacktschnecken omlet Cube

[jill the potter]

Hi,

 

My sister in America has just emailed me the following question:

 

"how do chickens know when eggs are fertilised so that they they can sit on them?"

 

I said that some broody hens will sit on any eggs fertilised or not, but apart from that my knowledge of hatching eggs is limited. Any answers please?

[C&T]

Chooks go broody regardless!

 

With fertilised eggs, unfertilised eggs, or no eggs...

 

As no-one has taught them the "birds and the bees", I guess they just do what comes natural, as if they were living with a cockerell?