Wearing a double helix tie with the now-faded signature of James Watson, the science-loving trustee of the New York Botanical Garden, Lewis Cullman, who has helped forge a collaboration between the garden and the American Museum of Natural History, spoke at a dinner Tuesday celebrating the garden’s new exhibit, “Darwin’s Garden: An Evolutionary Adventure.”

“Now we see, you can’t tell a plant from an animal,” Mr. Cullman said. “Some of you may think you’re a mushroom.”

Actually, most of the guests seemed content to be human at an event in honor of the 19th-century Englishman known for tenaciously documenting “survival of the fittest.”

“It’s the most highly civilized of occupations to understand how we evolve,” Nobel Prize-winning biologist Dr. Gerald Edelman said.

A great, great grandson of Darwin and a great nephew of the economist John Maynard Keynes, Randal Keynes, said, “A lot of people are hooked on Darwin. And I’m not just saying that because he’s my ancestor.”

Several guests said they would like to read Darwin’s work, but admitted their own passions may get in the way (Lady Salisbury tends to a roof garden in London, Amy Goldman is studying heirloom tomatoes).

For them and for us, the garden’s exhibit offers many fun ways to discover Darwin, including a re-creation of his own gardens, an outdoor plant tour with audio guide accessible via cell phone, and a beautifully rendered and updated Tree of Life.