Charles Darwin may be known as the Father of Evolution, but he was influenced heavily by many people throughout his life. Some were collaborators, some were influential Geologists or Economists, and one was even his very own grandfather. Below is a list of these influential men, and their work, that helped Charles Darwin shape his Theory of Evolution and his ideas of natural selection.
Jean Baptiste Lamarck was a Botanist and Zoologist who was one of the first to propose that humans evolved from a lower species through adaptations over time. His works inspired Darwin's ideas of natural selection.
Lamarck also came up with an explanation for vestigial structures. His evolutionary theory was rooted in the idea that life started out as very simple and built up until it was a complex human form. These adaptations occurred as new structures that would spontaneously appear, and if they weren't used they would shrivel up and go away.
Unfortunately, some principles Lamarck hypothesized were incorrect, even though Darwin did adopt some of those incorrect ideas at first. There is no doubt that Lamarck's ideas had a strong hand in what Charles Darwin officially adopted as his own ideas.
Thomas Malthus was arguably the most influential person on Darwin's ideas. Even though Malthus was not a scientist, he was an economist and understood populations and their growth or decline. Charles Darwin was fascinated by the idea that the human population was growing faster than food production could sustain. This would lead to many deaths due to starvation and how the population would eventually have to level out.
Darwin could apply these ideas to populations of all species and came up with the idea of "survival of the fittest". Malthus's ideas seemed to support all of the studying Darwin had done on the Galapagos Finches and their beak adaptations.
Only individuals of a species that had favorable adaptations would survive long enough to pass down those traits to their offspring. This is the cornerstone of natural selection.
Georges Louis Leclerc, Comte de Buffon was first and foremost a mathematician who helped invent calculus. While most of his works focused on statistics and probability, he did influence Charles Darwin with his thoughts on how life on Earth originated and changed over time. He was also ther first to really assert that biogeography was a sort of evidence for evolution.
Throughout Comte de Buffon's travels, he noticed that even though geographic areas were nearly the same, each place had unique wildlife that was similar to wildlife in other areas. He hypothesized that they were all related in some way and that their environments were what made them change.
Once again, these ideas were used by Darwin to help come up with his idea of natural selection. It was very similar to the evidence he found when travelling on the HMS Beagle collecting his specimens and studying nature. The Comte de Buffon's writings were used as evidence for Darwin while he wrote about his findings and presented them to other scientists and the public.
Alfred Russel Wallace did not exactly influence Charles Darwin, but rather was his contemporary and collaborated with Darwin on solidifying his Theory of Evolution through Natural Selection. In fact, Alfred Russel Wallace actually came up with the idea of natural selection independently, but at the same time as Darwin. The two pooled their data to present the idea jointly to the Linnaean Society of London.
It wasn't until after this joint venture that Darwin went ahead and published the ideas first in his book The Origin of Species. Even though both men contributed equally, Darwin with his data from his time in the Galapagos Islands and South America and Wallace with data from a trip to Indonesia, Darwin gets most of the credit today. Wallace has been relegated to a footnote in the history of the Theory of Evolution.
Many times, the most influential people in life are found within the bloodline. This is the case for Charles Darwin. His grandfather, Erasmus Darwin, was a very early influence on Charles. Erasmus had his own thoughts about how species changed over time that he shared with his grandson that ultimately led Charles Darwin down the path of evolution.
Instead of publishing his ideas in a traditional book, Erasmus originally put his thoughts about evolution into poetry form. This kept his contemporaries from attacking his ideas for the most part. Eventually he did publish a book about how adaptations result in speciation. These ideas that were passed down to his grandson helped shape Charles's views on evoultion and natural selection.
Charles Lyell was one of the most influential Geologists in history. His theory of Uniformitarianism was a great influence on Charles Darwin. Lyell theorized that geologic processes that were around at the beginning of time were the same ones that were happening in the current time as well and they worked the same way.
Lyell advocated for a series of slow changes that built up over time. Darwin thought this was the way that life on Earth also changed. He theorized that small adaptations accumulated over long periods of time to change a species and make it have more favorable adaptations for natural selection to work on.
Lyell was actually a good friend of Captain FitzRoy who piloted the HMS Beagle when Darwin sailed to the Galapagos Islands and South America. FitzRoy introduced Darwin to the Lyell's ideas and Darwin studied the Geological theories as they sailed. The slow changes over time became a description Darwin used for his Theory of Evolution.
7. James Hutton
James Hutton was another very famous Geologist that influenced Charles Darwin. In fact, many of Charles Lyell's ideas were actually first put forth by James Hutton. Hutton was the first to publish the idea that the same processes that formed the Earth at the very beginning were the same that were happening in the present day. These "ancient" processes changed the Earth, but the mechanism never changed.
Even though Darwin saw these ideas for the first time while reading Lyell's book, it was Hutton's ideas that indirectly influenced Charles Darwin as he came up with the mechanism of natural selection. Darwin said the mechanism for change over time within species was natural selection and it was the mechanism that had been working on species since the first species appeared on Earth.
While it is odd to think that a person who was very anti-evolution during his lifetime would be an influence on Charles Darwin's Theory of Evolution, that was exactly the case for Georges Cuvier. He was a very religious man during his life and sided with the Church against the idea of evolution. However, he inadvertently laid some of the groundwork for Charles Darwin's idea of natural selection.
Cuvier was the most vocal opponent of Jean Baptiste Lamarck during their time in history. Cuvier realized there was no way to have a linear system of classification that put all species on a spectrum of very simple to the most complex humans. In fact, Cuvier proposed that new species formed after catastrophic floods wiped out other species. While the scientific community did not accept these ideas, they were very well received in various religious circles. His idea that there was more than one lineage for species helped shape Darwin's views of Natural Selection.