How can genetic variations benefit a species? Give an example. PLEASE HELP

In which layer do organisms on earth love?

The greenhouse effect a. something that has occurred for millions of years b. an unnatural phenomenon caused by humans that maintains earths temperature range. c. the results of the differences in the angle of the suns rays d. an unnatural phenomenon that causes heat energy to be radiated back into the atmosphere

Stem cells found adult tissue such as in bone marrow brain muscle skin and liver are only capable of what