How We KnowAnswer
Why Can We Read Mammoth DNA but Not Dinosaur DNA?
A frozen mammoth tooth can hold readable DNA. A dinosaur fossil can preserve the shape of a bone for far longer. Here’s why those are different feats.
THE QUESTION LIBRARY HOW WE KNOW
Why do scientific studies sometimes contradict each other?
Why studies disagree: different questions, confounding, small samples, and honest interpretations. Learn how to compare evidence beyond headlines.
THE SHORT ANSWER
Studies can disagree because they ask different questions, study different people, use different methods, or get different results by chance. Finding an association does not by itself establish a cause. Honest experts may interpret uncertain evidence differently. The useful question is not which headline appeared last, but which explanation fits the strongest, most relevant evidence.
- Compare the actual questions before comparing headlines.
- Association does not establish causation.
- Honest disagreement can concern interpretation.
WHAT WE DON’T KNOW YET
The cause of any particular disagreement cannot be identified from headlines alone.
WHAT WOULD CHANGE THIS ANSWER
Independent, well-designed studies addressing the same populations and outcomes.
Studies can disagree because they ask different questions, study different people, use different methods, or get different results by chance. Finding an association does not by itself establish a cause. Honest experts may interpret uncertain evidence differently. The useful question is not which headline appeared last, but which explanation fits the strongest, most relevant evidence.
THE LONG ANSWER
THE LONG ANSWER · ABOUT 2 MINUTES
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Keep asking
Why Can We Read Mammoth DNA but Not Dinosaur DNA?
Cold ground can slow DNA’s breakdown enough for short fragments to survive.
New here?
God Plays Dice answers big questions in plain words, with sources and one of six honest labels.
Words worth knowing (2)
- confounding
- Another difference makes a comparison hard to interpret.
- sample
- The people or observations actually studied.
Sources & further reading
(4) · Checked Oct 5, 2026
- Reduced Mortality Risks and Correlation vs. Causation ↗NCCIH / NIH2015 methodological discussion; hypothetical coffee example is editorial, not a coffee-health finding.
- Pilot Studies: Common Uses and Misuses ↗NCCIH / NIHPilot feasibility differs from efficacy; small effects estimates unstable.
- How To Make Sense of a Scientific Journal Article: Discussion and Conclusion ↗NCCIH / NIHInterpretation may be disputed. Combined budget with Size of Study section: 200 words.
- How To Make Sense of a Scientific Journal Article: Size of the Study ↗NCCIH / NIHSmall samples may be inconclusive; combined guide budget 200 words.
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CONTINUE THE THREAD
Where this question leads.
How We KnowAnswer
Mutation by Natural Dominance: One Mutation or a Hundred?
If 100 bacteria carry the same DNA change, did it arise once or many times? The answer matters when testing Ricardo Maldonado’s hypothesis.
How We KnowAnswer
Are the colors in space photos real?
A space image can be faithful to measured light without matching human eyesight. Here is how to read the translation.