The three liquids will form three layers, the bottom layer is more dense and the top layer is less dense
It would be easier to put an image instead of explaining it. Here you are!
R = Red
r = white
RR = 25% - 25% chance of red
Rr = 50% - 50% chance of pink
rr = 25% - 25% chance of white
Invasive species is the easiest way to answer this, with invasive species the diversity will likely decrease