Question

Explain “fitness of a species” as mentioned by Darwin.

Answer 1

Hint: As described by Darwin, “fitness of a species” can be defined as the survival of the species heritable characteristics that lead to the production of more offspring. This fitness of species was determined based on the availability of limited resources in nature.

Complete answer:
As mentioned by Darwin, “fitness of a species” was best explained in the theory of evolution by natural selection. This theory states that the organisms having a stable reproductive capacity and the ones that can produce healthy offspring are more fit and thus have more chances of survival. Thus, the fitness of a species is the capability of a species to survive.

Additional information:
Charles Darwin in 1859 first formulated the theory of evolution by natural selection in his book titled “On the Origin of Species”. Evolution is the process by which organisms change over time as a result of physical or behavioral traits that are inherited from parents to offspring. These changes help the organisms to adapt to different environmental conditions that will help them to survive and have more offspring. Thus, Darwin’s concept of natural selection was based on several key observations:
-Characteristics or traits are heritable: In living organisms, many characteristics are heritable i.e., inherited from parent to offsprings.
-More offspring that can survive are produced: Species can produce more offspring that can be sustained by their environment. Thus, there is a competition between organisms for limited resources in each generation.
-Organisms vary from one another in their heritable traits.

Note: Charles Darwin defined evolution as “descent with modification” which means that species change over time, produce more offsprings, and share a common ancestor. The mechanism that leads to the process of evolution is natural selection.