Q. 20 - Biology

Question

Describe natural selection and give an example of natural selection at work in a population.

Step-by-Step Solution

Answer

Natural selection is an important evolutionary mechanism that aids in the modification of heritable features, which are passed down across generations.

Step 1 : Natural selection :

It is described as a process in which organisms reproduce and survive in diverse ways as a result of phenotypic alterations. It comprises a mild variation of a trait, which is retained if the variance benefits the individuals. 

Step 2 : Explanation :

Natural selection can occur in a predictable or ad hoc manner. As a result, it may be classified into the following categories:

Directional selection

Stabilizing selection

Disruptive or Diversifying selection

Kin selection

Sexual selection.

Natural selection, together with mutation, migration, and genetic drift, is the primary mechanism of evolution. Natural selection may be shown in the following examples:

$1$. There are red and green bugs in a habitat. The birds prefer the taste of just red bugs, therefore as the process continues, the green bugs generate more green bugs, while the quantity of red bugs decreases.

$2$. In an ecosystem, some giraffes have long necks while some have short necks. However, food bushes are available at a good height. As a result, giraffes with short necks would eventually run out of food and die out. However, only a few generations of long-necked giraffes survive.