Final answer:
The book 'On the Origin of Species,' which introduces the theory of evolution by natural selection, was authored by Charles Darwin in 1859. Darwin's research on his voyage aboard the HMS Beagle, especially in the Galapagos Islands, was fundamental in the development of the book. The correct answer is (a) Charles Darwin.
Step-by-step explanation:
In response to the prompt regarding the author of On the Origin of Species, the book is attributed to Charles Darwin. Published in 1859, On the Origin of Species presented the groundbreaking theory of evolution by natural selection. While both Charles Darwin and Alfred Wallace contributed to the development of the concept, it was Darwin who extensively detailed these ideas in his seminal work. Darwin described how certain traits become more or less common in a population due to the organisms with beneficial traits reproducing more successfully. This book only included one illustration, a diagram that demonstrates how species evolve over time through natural selection.
Charles Darwin's observations during his voyage on the HMS Beagle, particularly in the Galapagos Islands, greatly influenced his ideas on natural selection. His examination of the unique flora and fauna there played a crucial role in the formulation of his theories. Therefore, the correct answer to Thom's statement about the author of On the Origin of Species is (a) Charles Darwin.