I know a lot about animals. A really cool thing i learned about is how some animals sleep with half there brains. For example the dolphin does not breath automatically like we do. If they were to sleep completely they would die because they forget to breath. Also predators might try and attack in the night so they have to stay alert. Dolphins alternate sides of the brain to make sure the both sides get rested up.

Another example would be the duck. These animals can sleep with half there brain or all of it. Ducks sleep in groups so the two ducks on the outside are the ones that sleep with half there brain. They keep one eye open and one eye closed. This way they can see predators. The ducks switch sides of the brain too. The ducks right eye is connected to the left part of the brain. A ducks left eye is connected to the right part of the brain. When the switch they switch eye so they turn to keep there eyes on the outer side of the log. In the mean time the other ducks are sleeping there in tire brain.

We humans do not have this ability. Some scientists think that the reptile that we originated from had this ability then when it came on land it found a cave and adapted to be able to sleep both haves of there brain. It did this they think because it had no predators in the cave. Then this animal evolved into a mammal. Along the way into bigger mammals and primates we lost the ability to sleep with half our brains because we did not need to.