The natural water sample contains only one type of bacteria.
The answer is natural selection.
In natural selection, genotype variations that will increase the chance
of survival and reproduction of some organism are preserved and will be
inherited. Red and green colors of butterflies increased the chance of their <span>survival and reproduction, so these traits will pass to the next generation.</span>
<span>The Cerebrum: The cerebrum or cortex is the largest part of the human brain, associated with higher brain function such as thought and action. The cerebral cortex is divided into four sections, called "lobes": the frontal lobe, parietal lobe, occipital lobe, and temporal lobe.</span>