<span>The extracellular fluid would have more salt. This would be because more of the sodium would be found in the blood than in the cells. Keeping a static level of sodium in the bloodstream is necessary for the proper cell activities, but increasing sodium intake can lead to negative effects.</span>
Global warming is the answer
The answer is reproductive isolation. Reproductive isolation ensures members of different species do not produce offspring. In this case, geographical separation is ensuring that individuals from the two different populations are not able to mate with each other. Eventually, through different selective pressures, the two populations will diverge sufficiently in genotype to become distinctly different.
I think its reproductive cells like egg or sperm