Why do the winter and the summer alternate?

When the noble ocean was only mud,when the stately mountain was only a mound, a Father-Frost and a Father-Warmth decided to show each other who was mightier.

"I will change this world into ice in just nine days, can you melt it?"asked the Father-Frost.The Father-Warmth replied,I can melt all the snow and the ice into an ocean!You can not obstruct my heat and warmth."Then they agreed the see who would take control over the other.
The Father-frost made a snow storm which lasted for nine days,freezing the world by its unusual coldness, and he created a great bull to defend it (his creation).Then the Father-Warmth made the sun shine for eight days, basking the world in heat from all sides and it melted the snow into a great ocean.

When the Father-frost and Father-Warmth checked together to see if there was any ice left, they found some under the four solid hooves of the bull.The ice left under its two front legs was Antarctic Ocean.The Father-Warmth saw them, became angry and cut the solid hooves off the bull, because of this the cow has got cloven hooves.However,as the two old men's power was equal they divided up the year evenly and they agreed to alternate the summer and the winter around it.