On the occasion of Charles Darwin's 200th birthday, Feb. 12, Cornell President Emeritus Frank Rhodes said in a public talk: "In one way or another, we all are beneficiaries of this good and gentle and caring and wise and generous man, one of the great pillars of modern knowledge."

More than 200 people packed Hollis E. Cornell Auditorium in Goldwin Smith to hear Rhodes, a widely cited paleontologist and Darwin scholar, speak about the great naturalist's life and legacy.

Rhodes' talk opened the exhibition, "Charles Darwin: After the Origin," a collaboration between Cornell and the Museum of the Earth, which will be displayed in Kroch Library's Hirshland Gallery through Sept. 8.

When Darwin left for his famous voyage on the HMS Beagle, he was still an inexperienced, "fresh" student, but he returned to England five years later "a seasoned naturalist," haunted by three questions that he would ponder for the rest of his life, Rhodes said.

Darwin had seen vertebrate fossils of extinct species intermingled with those that were still living, which made him wonder about the separation in time between species.

In Patagonia, he observed that rheas (flightless birds, one of which he ate for Christmas dinner) were distinctive from rheas he had seen further north. These differences got him thinking about what could be responsible for the geographic separations between species.

Finally, Darwin started wondering about the transmutation of species after making his famous observations of finches and tortoises in the Galapagos Islands. "'It is as though one species had been created and modified for certain aims,'" Rhodes quoted from Darwin's journals.

It took many years of ruminating before Darwin arrived at what would become his theory of evolution.

"I can remember the very spot on the road, while still in my carriage, when to my joy the solution to the problem came to me. Here we have a theory with which to work," Darwin wrote.

"This became Darwin's brooding secret," Rhodes said. "The notebooks expanded, the correspondence grew, but Darwin hesitated to publish," he said.

Worried about his work being premature and concerned about the religious implications of his theory (especially for his wife, who was a devout Christian), Darwin did not publish his ideas immediately. It was not until he learned that the naturalist Alfred Russel Wallace had developed the same ideas that Darwin was "panicked into publication," Rhodes said.

Darwin published his famed "On the Origin of Species" in 1859, and wrote several additional books thereafter.

"He published at a prodigious rate," Rhodes said, citing that Darwin published more than 10,000 pages over 42 years.

When an audience member asked Rhodes to what extent scientists believe in evolution, he responded, "one of the early problems with a belief in evolution was that no one had seen it happen." Also, scientists did not know "whether there was enough geologic time for it to happen, and what was the mechanism for evolution," he said.

"In each of these three cases, the evidence is now conclusive," Rhodes explained. "One can choose to say that the evidence is not overwhelming, but I think now it stands at least comparable to other substantial scientific theories. It is possible to disbelieve in gravity, but what we live every day does demand a certain assumption that it is correct," he added.

Rhodes concluded his talk with a message for Darwin: "Happy birthday, Charles. We salute you!"

Graduate student Melissa Rice is a writer intern at the Cornell Chronicle.