The original boundary between the states of Nebraska and Iowa was the Missouri River. The border departs from the river channel because the river's course moved eastward many years after the boundaries were established.
Explanation:
The boundary between Nebraska and Iowa was the Missouri River. In 1877, the river course moved, and a town called Carter Lake on the Iowa side is now on the Alaska side. Even though Alaska claimed the land, the Supreme Court stated that the area belongs to the state of Iowa. That is why the boundary departs from the river channel.
In near the equator we experience 12 hours of daylight as the equator is situated exactly the halfway in between the two poles. The North pole experiences long daylight in the months, when the North Pole is tilted towards the Sun and shorter daylight when the pole tilted away from the Sun. The reverse is true for the Southern Poles. But this wouldn't have any effects in daylight on the equator.