what are 3 observations made by dawin that puzzled him and led him to the fumulation of his theory?

Answer 1

Darwin's observations

All species have such great potential fertility that their population size would increase exponentially if all individuals that are born go on to reproduce successfully.
Populations tend to remain stable in size, except for seasonal fluctuations.
Environmental resources for things such as food and shelter are limited.
Individuals of a population vary extensively in their characteristics (to the extent that no two individuals are exactly alike) which impacts upon their own ability to survive and reproduce.
Much of this variation is genetic and is therefore heritable.
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