A species of fox lives in the arctic where the ground is covered in white snow most of the year. These arctic foxes hunt rodents and other small mammals, while their predators include eagles, wolves, and polar bears. A mutation in its DNA causes a fox to have white fur rather than brown. Given this information, would you classify this mutation as a harmful, beneficial, or neutral mutation? Would this make the fox more or less likely to survive? Explain your answer.

Question

Put the answer in depth

Answer 1

In the context of the arctic fox living in a snowy environment, the mutation that causes an individual fox to have white fur rather than brown can be classified as a beneficial mutation. This classification is based on the following factors related to survival and adaptation in its specific habitat.

Camouflage

1. Predation: The primary advantage of white fur in an arctic environment is related to camouflage. When the ground is covered in snow, a white-furred fox is less visible to both its prey (small mammals like rodents) and its predators (eagles, wolves, and polar bears). This enhanced camouflage increases the fox's ability to hunt effectively while reducing the chances of being detected by larger predators. Effective camouflage is fundamental for survival, particularly in an ecosystem where survival hinges on both predation and avoiding becoming prey.

2. Hunting Efficacy: With white fur, the arctic fox can blend into its environment, allowing it to ambush its prey more effectively. The ability to hunt successfully increases the fox's chance of obtaining food, thus supporting its health, reproductive success, and overall fitness within the population.

Genetic Adaptation

3. Natural Selection: In the environment where these arctic foxes live, the ability to blend in with the snowy landscape would offer a significant selective advantage. Over successive generations, individuals with the white fur trait would likely reproduce more successfully than those with brown fur, assuming the brown-furred variant does not have some compensatory advantage under different circumstances (such as during seasons with less snow, which are typically rare in the Arctic).

4. Seasonal Changes: While it is worth noting that some areas may experience variations in snow cover, the arctic fox has also adapted behavioral traits such as seasonal molting. Arctic foxes can change their fur color to a darker shade in the summer months when the snow melts, allowing them to retain camouflage year-round. This further underscores the adaptability of the species; thus, the mutation for white fur remains advantageous during the majority of a year when snow is present.

Conclusion

Given these factors, the white fur mutation increases the likelihood of survival for the individual foxes that possess it. The environmental context dictates its benefits, demonstrating the principle of natural selection, where traits that enhance survival and reproductive success become more prevalent in the population over time. Therefore, in the case of an arctic fox with white fur, it can be classified as a beneficial mutation that enhances its overall fitness within its habitat. In summary, the mutation serves as an advantageous trait that improves the fox's chances of surviving and proliferating in a challenging and competitive ecological niche.