A population of Poison dart frogs can be red (RR), orange (Rr) or yellow (rr). The allele frequency of the mainland is R: 0.5 r: 0.5. A small group of the frogs moves to an island off the mainland. If the group is composed of 4 red and one orange frog, what would you expect to happen to the allele frequency?

there are so many examples for that in different areas, like biology experiment carried out in our lab recently.

here's one link:

answer: ice crystals in air

the water from the water body or another source of water gets evaporated as water vapor as an effect of heat on water. these water vapor rises in the upper layers of the earth atmosphere under high atmospheric pressure. the atmospheric pressure of these water molecules starts to decrease due to the effect of cold air. the invisible water vapor condenses into visible water droplets and ice crystals.these ice crystals and water droplets being less denser than the surrounding air floats on air as clouds.