Final answer:
Icefishes have variations of antifreeze proteins, with the high amount being the most favorable trait in their cold environment. Natural selection selects for icefishes that produce high amounts of antifreeze proteins. Over time, the icefish population in very cold waters will increase in individuals with high antifreeze protein production, resulting in an adaptation in terms of allele frequency and reproductive fitness.
Step-by-step explanation:
The different variations of antifreeze proteins present in the population of icefish are high, medium, and low. These variations are produced in different amounts in different icefish species.
The most favorable trait in the environment of the icefish is the high amount of antifreeze proteins. This trait helps the icefish live in the cold waters by preventing ice crystal formation in their blood.
Natural selection will select for icefishes that produce a high amount of antifreeze proteins. This is because the high amount of antifreeze proteins is the most advantageous trait for survival in the cold waters of the southern ocean.
Over time, the icefish population in very cold waters is likely to increase in individuals that produce a high amount of antifreeze proteins. This is because these individuals have a better chance of surviving and reproducing in the cold environment.
The adaptation in icefish can be observed in terms of allele frequency and reproductive fitness. The allele for producing a high amount of antifreeze proteins will become more common in the icefish population over time, resulting in an increase in allele frequency. This adaptation increases the reproductive fitness of icefish, as individuals with a higher amount of antifreeze proteins have a better chance of surviving and reproducing in the cold waters.