The Abaco Islands. The Abaco Islands consists of several islands and cays (very small islands) that are great for exploring and snorkeling. Andros Island is the Bahamas' largest island but it's also the least developed. Like other Out Islands, Andros Island is ideal for eco-travelers.
bottleneck (bÅt'l-nÄk') An abrupt and severe reduction in the number of individuals during the history of a species, resulting in the loss of diversity from the gene pool. The generations following the bottleneck are more genetically homogenous than would otherwise be expected. Bottlenecks often occur in consequence of a catastrophic event.
There are two major types of genetic drift: population bottlenecks and the founder effect. A population bottleneck is when a population's size becomes very small very quickly. This is usually due to a catastrophic environmental event, hunting a species to near extinction, or habitat destruction.enetic drift is when chance events cause changes in frequencies of alleles in a population. Alleles are the genetic variations in a population, and they are the driving force behind the evolution of that population. The smaller the population, the greater the impact genetic drift will have.