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5. Life
What makes life so special? Is there life elsewhere in the Universe? And how exactly did life emerge and diversify? In many ways these remain mysteries, but we do have enough evidence to explore some possible answers.
All content in “5. Life”

5.0—What Is Life?

Among living things, there are strong similarities and remarkable differences, many explained by the amount of shared DNA. But what does that really mean? What is life?

5.3—Ways of Knowing: Life

Life can be fragile. The continued existence of a species can depend on even the slightest changes to astronomical, geological, and biological conditions.


Review Big History vocabulary and take the glossary challenge.


Download the teacher resources from the Big History Project classroom version of this course. Text transcripts for videos are also available.