A bottleneck is very narrow, which means that only a portion of the contents of the bottle cat get out (at the time).
From this effect, people use the word bottleneck when only a few individuals of a population survive:
the answer is: I<span>nsecticide spraying eliminates all but a few of the beetles on an island.</span>
The flooding of half part of the forest have successful separate the population of frogs in that ecosystem into two different set of frogs. This is an example of allopatric speciation, that is, the population become separated as a result of geographical barrier. This separation will make the two set of frog population to become new species. On the long run, the two species may become unable to relate sexually.
The answer would be ''Y-Chromosomes Analysis''
