Imagine you are studying a population of finches on one of the Galápagos Islands. You have been recording many of the birds' physical traits, including the length of both wings. You observe that for 80% of individuals measured, the length of the left wing is not significantly different from the length of the right wing (in other words, they are symmetrical). But for about 20% of birds measured, the wing lengths are asymmetrical. This distribution is true from generation to generation. Suddenly, a rare 5-day windstorm takes over the island. After the storm, you spend the next several days netting each bird on the island that survived the storm. You discover that 85% of the birds with symmetrical wings survived the storm, whereas only 5% of the birds with asymmetrical wings did. a. Propose a hypothesis to explain this observation.
b. If such storms become increasingly common due to changes in climate, how might you expect the population to change over time with respect to wing symmetry? The distribution of symmetrical to asymmetrical will change so that close to 100% of birds will have symmetrical wingspans.

Natural selection benefits the phenotype that increases the fitness. a) Symetrical wings increase the fitness of finches because they are better to face selective pressures. b) natural selection will favor symmetrical wings.

a) Hypothesis:

Symmetrical wings increase the fitness of finches because these type of wings are better to face selective pressures like severe windstorms.

b) If such storms become increasingly common with time, natural selection will favor symmetrical wings by increasing its frequency in the population, while animals with asymetrical wings will decrease to near cero.

Natural selection is an evolutive force that selects beneficial alleles and increases their frequency in the population. It is the result of the phenotype-environment interaction which determines gene destiny in space and time. Natural selection results in adaptation, which means the increase of the aptitude phenotype. Aptitude is the contribution of each genotype to the next generation.  Aptitude (or fitness) is reflected by the phenotype that results in the survival, fertility, and capability of having a mate.  Adaptations can be correlated to environmental factors or selective pressures applied by other organisms or habitats. The selective agent is the environmental trait that determines the differential survival of the phenotypic classes. The environment influences the probability that each genotype passes its gametes to the next generation.

So in this example,

⇒ The strong storms are acting as selective pressures.

⇒ This selective pressure is modeling the phenotype of finches.

⇒ Natural selection favors the phenotype that performs better when facing storms.

⇒ Symmetrical wings are the phenotype that better suits and increases the animal's fitness.

⇒ Hence, natural selection favors this phenotype over asymmetrical wings.

Realted link: link

                     link

a) The change in the character of an organism relies upon the ability of the adaption on the base of the external change or the environment change, "An organism that is not able to adapt accordingly would not survive and eliminated from the population."

b) In the given case, Symmetric wings are far more suitable for the survivorship as it provides better flight than the organism with asymmetric wings, it is also given that there is 20% of the population have asymmetric wings.

After the storm which is selection pressure, there is the elimination of the entire bird population with asymmetrical wings from the ecosystem so the final frequency would be 100% of the entire population with symmetrical wings.

Explanation:

H is a gass