15. Which of the following is an example of a pioneer species in secondary succession?
a. Lichens
b. Grass
C. Insects
d. Shrubs

it's anything that aren't producers and consumers.

explanation:

you've got to be clear on what "this" is

yes it is   dangerous

explanation:

because that foot is discusting and could get you sick

the answer is c.) there is a warm front in region a and a stationary front in region b.

the cladogram shown here shows similarities and differences among several classes of vertebrates. anatomically, the four have limb structure as their common ancestor. we might separate the mammals from the other three classes because they a) divergent; do not lay eggs b) identical; are warm-blooded c) varied; a four chambered heart d) homologous; have mammary glands