Biology · Evolution · NEET
Evolution is the process: the change in flora and fauna over millions of years. Evolutionary Biology is the subject that studies this process, that is, the study of the history of life forms on Earth. So evolution is what happens; evolutionary biology is how we study it. NEET questions often quote the NCERT line 'Evolutionary Biology is the study of history of life forms on earth,' so remember it word for word.
No. Origin of life is how the first life started from non-living matter. Evolution is the change and diversification of life AFTER it already exists. The NCERT chapter covers both together, but they are separate ideas: first life originates, then it evolves into many forms. Do not write 'evolution = origin of life' in NEET; that mixes two topics.
No. A single organism does not evolve. Evolution happens over generations in a population of organisms across long time (millions of years). One rabbit does not evolve, but the rabbit population changes over many generations. This is why evolution is always described as change over time, not change within one lifetime.
NCERT says to understand changes in living things over millions of years, we must first understand the context: the origin of the universe, of stars, and of Earth. Life evolved on Earth, and Earth itself formed from the universe. So the chapter builds a timeline: universe first, then Earth, then origin of life, then evolution of life forms (biodiversity).
Biodiversity means the variety of life forms on Earth. NCERT calls the chapter 'the story of origin of life and evolution of life forms or biodiversity on planet earth.' So biodiversity is the RESULT of evolution: because life kept changing and branching over millions of years, we now have millions of different species.
Try the real previous-year questions from this chapter — each with the answer and a full solution.
Evolution is the change in flora and fauna (living forms) over millions of years, leading to new life forms from older ones. It is a slow, continuous, generation-to-generation process, not a change within one organism's life.
NCERT defines Evolutionary Biology as 'the study of history of life forms on earth.' This exact line is commonly tested, so memorise it.
For NEET, treat evolution as the observed process of change in life forms over time, supported by strong evidence (fossils, homology, molecular data). Theories like Darwin's natural selection explain HOW evolution happens; evolution itself is the change that these theories explain.
It is the chapter opener and sets the timeline: universe to Earth to origin of life to evolution of life forms. Getting the meaning right helps you separate origin-of-life topics from evolution topics, which NTA often mixes up in questions.
