The Physics Behind Why Sausages Split Lengthwise

I like sausages. I like grilled sausages. I like fried sausages. I like beef, pork and chicken sausages. I even like vegetarian sausages. Sometimes when you cook sausages, they burst. This occasionally happens if you try and cook them too fast. It can also happen if the brand of sausage you are cooking is overly generous with their filling.
The Physics Behind Why Sausages Split Lengthwise