What will occur if a species is divided into two groups and allowed to reproduce in different environments for many generations a. random mutations, all of which will decrease fitness
b. divergence, potentially giving rise to two different species
c. divergence, but these will never be two different species
d. natural selection, keeping both groups genetically static

If someone could do the first couple, just so i can see how it's done that would be great! 20 points. complete a dichotomous key for the 10 leaves on the common leaves sheet. the chart provided here allows for 11 pairs of statements. depending on how you build your dichotomous key, you may or may not need all of them, or you may need to add some.

Consider the model of the oxygen cycle on earth. the majority of earth's oxygen reservoirs are found in the a) atmosphere. b) biosphere. c) hydrosphere. d) lithosphere.

8) animals respond in various ways to stimuli detected through their senses. some of these responses are stimulated by the presence of danger. which of these animal responses is the best example of a response to an immediate threat? a) a rooster crows every morning at the first sign of light. b) as something approaches an octopus, it shoots a cloud of ink. c) from late fall until spring, bears hibernate to preserve energy. d) a dog is getting hot in the sunlight, so he moves to a shaded area.