What is the concept of survival of the fittest.

Which of the following types of rock would most likely contain a fossil? slate granite lava rock limestone

When a population split into two subgroups what is most likely to cause the subgroups to develop different traits?

There are few cells in the body that do not undergo mitosis: most somatic cells divide regularly, some more than others. take for example the cells that line the digestive tract. these cells must be frequently replaced because they are constantly eroded by the movement of food through the tract. what mechanism(s) is/are in place to ensure that these cells are exact copies of the mother cell