Explain how the scientists' findings impacted the developing theory of evolution and relates to the modern theory of evolution.

Scientists: Charles Darwin, Steven Gould, Ernst Mayr, and Ronald Fisher

And if you could also provide information on how their findings and publications relate to the commonly held beliefs of the day, it would be greatly appreciated.

Charles Darwin is the creator of the evolution theory, which states that organisms evolve by survival of the fittest. This theory is central in biology and enables to understand how species are formed and biodiversity generated

Steven Jay Gould was a paleontologist that developed the theory of the punctuated equilibrium, which indicated that evolution is characterized by long periods of stability periods followed by the sudden emergence of new species

Ernst Mayr was an evolutionary biologist who developed the biological species concept, which is critical to understand the mechanisms of speciation

Ronald Fisher is considered to be the founder of population genetics. His work was critical to understand the association between Mendel's Laws and Darwin's theory