300 BC by Greek philosophers
The term is called THEORY.
In scientific investigation, a theory is a well substantiated explanation of how a particular phenomenon works based on the set of facts which had been repeatedly confirmed through observations and experiments. A scientific theory gives reliable account of a phenomenon.
Bacteria are so successful because they reproduce asexually meaning that they can make more offsprings at a shorter amount of time. Because they reproduce asexually, if that one bacteria is resistant to a certain other organism, so will its offsprings.
Energy from the Sun fuels life on Earth.
Sunlight allows plants, algae and cyanobacteria to use photosynthesis to convert carbon dioxide and water into organic compounds like carbohydrates. This process is the fundamental source of organic material in the biosphere.
