CHICAGO--Out on a beetle-collecting stroll, Charles Darwin faced a dilemma: He had one  interesting beetle captured in each fist when another prize specimen caught his eye. What did he do?

"I popped one in my mouth," Darwin interpreter Brian "Fox" Ellis said, drawing groans and laughter from his audience of middle school students gathered at Chicago's Field Museum for AAAS's Public Science Day. "Until it emitted a fluid which burnt my tongue, so that I was forced to spit it out!"

In character as a young Darwin, Ellis shared tales from the naturalist's explorations with more than 200 Chicago-area students and their teachers, showing how Darwin slowly built his theory of natural selection. But other aspects of the scientist's life--his struggles with his father, the strong influence of beloved teachers, and what to pack on a trip around the world--seemed to engage the audience as much as stories about fossils and orchids.

Billed as the "Middle School Science Summit on Evolution," the 11 February event co-sponsored by AAAS and the Field Museum was open to the public and promoted specifically to schools as part of AAAS's ongoing committment to public science learning. To celebrate the 200th anniversary of Darwin's birth, students explored the museum's halls and delved into its collections.

Middle school is the time when students may first encounter the concept of evolution, "but we're fighting tough odds here," said Shirley Malcom, head of Education and Human Resources at AAAS. She cited surveys suggesting many American adults do not believe in that the human species has evolved. "If we're able to introduce the processes by which evolution happens," explained Malcom, "we can help keep young people's minds open in later grades."

Before Ellis's appearance, students from John M. Smyth Magnet School said they were starting to talk about evolution in their science classes, "when we've been talking about cells and bones," said Smyth student Larkey Goodwin.

Goodwin and his friends were looking forward to their tour of the museum's back labs. Smyth science teacher Michael Richie said the class had visited the Field Museum a month earlier, and he was afraid the students might ask, "'why are we here, we've seen this all before,'" he said. "But what really excited them was the idea that they were going behind the scenes."

High in the collections attic of the museum, sixth graders from Armour Elementary School soon had their hands full--literally--of Chilean rose hair tarantulas and Madagascar hissing cockroaches. The students bombarded collections specialist Jim Louderman with questions about the animals: Are they poisonous or venomous? Can you eat a beetle? Why do these butterflies look like dead leaves?

"I never thought I would come over here and see this part," said Armour student Maria Hernandez, who asked Louderman about the mysterious disappearance of honeybees around the world.

"I think it's fascinating how animals live their own lives," Jackie Vargas agreed, scribbling notes for her school report. Both girls said they would consider becoming scientists one day.

Events like Public Science Day help the Field Museum build relationships with students that might not occur during a regular field trip, said Laurel Ross, the museum's urban conservation director.

"We're not all going to become scientists," she said, "but any step away from an anti-science feeling is good."

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