ANATOMY

Detailed explanation-1: -Natural selection, also known as “survival of the fittest, ” is the more prolific reproduction of individuals with favorable traits that survive environmental change because of those traits. This leads to evolutionary change, the trait becoming predominant within a population.

Detailed explanation-2: -In the first four editions of On the Origin of Species, Darwin had used the phrase “natural selection". In Chapter 4 of the 5th edition of The Origin published in 1869, Darwin implies again the synonym: “Natural Selection, or the Survival of the Fittest".

Detailed explanation-3: -An adaptation is any heritable trait that helps an organism, such as a plant or animal, survive and reproduce in its environment.

Detailed explanation-4: -Survival of the fittest means that organisms that are better adapted to their environment are best suited to survive and successfully reproduce. “Survival of the fittest” is an expression, developed from Darwin’s theory of evolution.

Detailed explanation-5: -The Principles of Biology by Herbert Spencer (1864) looked at biology in terms of themes, such as Function, Adaptation and Variation. In this book Spencer introduced the expression ‘survival of the fittest’, in the sense of ‘the most appropriate to its environment’.