<span>The loss of the gene coding for an orange crest in the bird population described above is an example of <span>genetic drift.
</span></span><span>Genetic Drift is the change in the frequency of an allele in a population due to random sampling of organisms.</span>
They can all travel through empty space
The root word of Unicellular already tells you the answer. Uni means only one cell. So the answer is one cell.