By primary succesion. Which is when new substrate is deposited.
One thing that separates us from the other animal classifications is that we have hair, everywhere! :D The next major difference is the fact that mammals don't lay egg's, we give birth to live creatures. Those are the 2 biggest things that distinguish us from them.
Hope I helped. :)
Generally, the sun observes a solar cycle of eleven years. In this cycle, there are fluctuations in the activity, such as the ejected levels of solar radiation, and in the appearance of the sun, such as changes in the amount and size of sun spots, solar flares and other phenomena that occur on the sun's surface.
These changes also affect phenomena on earth, especially the auroras.