Flowers have evolved to fit the bills of female (above) and male (below) hummingbirds—and the birds have evolved to fit the flowers.
By Sarah Auerbach '96
The hummingbirds and flowers that Ethan Temeles studies belong together so profoundly that they have evolved to fit each other better. That’s a bit like the relationship that Temeles, an associate professor of biology at Amherst, has with the Smithsonian National Museum of Natural History, where his research is now featured in a permanent exhibition, Butterflies and Plants: Partners in Evolution.
In 2000, Temeles and his students discovered that male purple-throated carib hummingbirds prefer a species of heliconia flower that is perfectly tailored to their bill shape, while
their female counterparts, whose bills are shaped differently from those of the males, favor a different species of the flower—one that matches their own bill shape. As Temeles also found out, when the male’s favorite heliconia was rare or absent, the female’s favorite heliconia began to produce two different kinds of plants—one that appealed to females and one that appealed to males. It was the missing piece of evidence scientists needed to show that the flowers were evolving to fit the birds and vice versa. Temeles’s findings were published in Science magazine.
John Kress, an expert on heliconia flowers who was then head of the Smithsonian’s botany department, read about the research and was impressed. He and Temeles began a collaboration that yielded a second piece in Science, a 2003 cover story.
When the Smithsonian built a butterfly pavilion last year, curators decided to feature evolution research by Smithsonian scientists, including Temeles and Kress. “It was a great fit,” says Sally Love Connell, the exhibit’s developer.
Temeles spent the 2006-07 academic year, his sabbatical, at the Smithsonian. In February 2008, he returned to Washington for the opening of the permanent exhibition. At the center of the exhibit stands a tube-shaped greenhouse filled with butterflies. Outside the pavilion are painted panoramas—“wonderful artwork of the hummingbirds and the flowers that we’ve studied,” Temeles says. There are also specimens from the museum and questions for children, asking them to guess which bill might fit which flower.
Temeles isn’t the only Amherst professor to figure in the exhibit. Lincoln Brower, who taught at Amherst during the ’60s and ’70s, researched monarch butterflies and milkweed, another co-evolving pair. “So here you have this hallway where there’s something like five exhibits, and Amherst College accounts for two of them,” Temeles says. “You walk in there and you realize, My God, here we are, little Amherst College, and you realize the biology here is pretty good.”
Photos courtesy of Ethan Temeles