According to darwin's theory of evolution, how does natural selection cause species to evolve over time?

As time goes on, members of a population with favorable traits continue to breed while those without these traits eventually die off. For instance, if all of the food in an area was high up in the trees, only members of the species with long necks are able to eat and continue to live and reproduce. Those with shorter necks will not be able to eat and will eventually die off. Over time, the species will evolve to have long necks.

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kepler used the data from tycho blahe (his mentor) to construct the laws of planetary motion.