Science and Its Evolving Nature
Understanding how scientific knowledge changes and grows over time.
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Historical examples show this clearly: for centuries, people believed diseases were caused by 'bad air,' until the discovery of microorganisms (germ theory) completely changed medicine. Even today, scientific understanding of things like nutrition, space, and genetics continues to be refined as new research emerges. This is why science relies on peer review — other scientists checking and testing each other's work — to ensure only well-supported ideas become widely accepted.
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• Science evolves as new evidence and better tools become available.
• The heliocentric (Sun-centred) model replaced the earlier Earth-centred model of the solar system.
• Germ theory replaced the earlier 'bad air' theory of disease.
• Peer review helps ensure only well-tested scientific ideas are widely accepted.