The bottleneck effect can be explained by the cheetah population. Cheetah's used to be unique and many before they were hunted. Their population dropped so low, breeding produced almost exact 'clones'. The bottleneck effect is when genetic diversity is lost.
<span>Standard deviation is the square root of variance. Variance is always a non-negative number, since you can't take the square root of a negative number. So neither can be negative </span>
