December 22, 2009
Tiny birds will be the big stars of an episode of Nature airing Jan. 10 on PBS. The episode will feature the hummingbird research of Ethan J. Temeles, professor of biology at Amherst College.
The show, titled “Hummingbirds: Magic in the Air,” will feature Temeles’ research on the purple-throated carib hummingbird on the island nation of Dominica. The film is spectacular for its high-speed cinematography: viewers can literally see hummingbirds trying to kick each other as they squabble over food and get birds’-eye views of them feeding from flowers.
“It’s a great opportunity for the Amherst community to visit the Caribbean and see what I've been doing for the last 11 years,” Temeles says.
The aspect of Temeles’ research that is being covered in the show explores sexual dimorphism in hummingbird bills. In a 2003 article that appeared in Science, Temeles and colleague W. John Kress of the Smithsonian Institution reported that the shape and length of the bill of the female purple-throated carib hummingbird has evolved differently from the bill of the male, to better fit the flowers that provide the birds with nectar. At the same time, the flowers of their two Heliconia food plants have adapted to the bills of the birds that are their means of reproduction.
“My studies of the purple-throated carib hummingbird provide the strongest evidence to date for Darwin’s ecological causation hypothesis, by linking sexual differences in trophic morphology to sexual differences in resource use,” Temeles says.
This species of hummingbird exhibits one of the most pronounced sexual dimorphisms in bill size and shape of any avian species. Males are 25 percent heavier than females, yet the bills of females are 20 percent longer and 40 percent more curved.
The PBS Nature episode will provide viewers with a three-to-four-minute summary of Temeles’ research.
“Viewers get really great looks at the bills of male and female purple-throats, as well as their food plants,” Temeles says, “and me in the rain forest in my raincoat—it was pouring the day they filmed me!”