Final answer:
Charles Darwin applied Thomas Malthus's observations on exponential human population growth and limited resources to the natural world, developing the concept of evolution by natural selection where organisms with favorable traits are more likely to survive and reproduce.
Step-by-step explanation:
Charles Darwin was significantly influenced by the ideas of Thomas Malthus, an English clergyman, and economist, in developing his theory of evolution by natural selection. Malthus's observations of exponential growth in human populations and the consequent struggle for resources due to slower food production increases, helped Darwin realize a similar process occurring in nature.
Darwin understood that in any given environment, more offspring are produced than can survive, leading to a struggle for existence. Those with favorable traits are more likely to survive and reproduce, passing those traits on to subsequent generations.
This mechanism of differential survival and reproduction, termed natural selection, is the core of Darwin's evolutionary theory. It explains the adaptation of organisms to their environment over time and the emergence of new species. The connection between the Malthusian concept of population growth versus resource limits and Darwin's concept of the survival of the fittest illustrates a pivotal moment in scientific understanding of biological diversity.