Why does this happen to my fruit?

Question

http://www.imagebam.com/image/039a5c11104395

This not only happens to my oranges (That is a navel orange), but my other citrus fruits as well. Does anyone know what is happening or why?

Answer 1

I know for a fact tomatoes will split like that due to lack of water. When fruit develops it needs tons of water- Most fruits are 75% water.