Why are orange cats orange?

[Catherine]

When I had a cat I always had white hair on my clothes and everywhere else. I can imagine it is like snow storm of hair as the weather warms up.
Edward will enjoy the warm days though, once all his extra hair is gone.
The vacuum hasn't been invented that can keep up with a shedding cat.

There are more ginger male cats than ginger female cats. That may be why the scientists were curious. 
They wanted to know why.