Giant 'gentle spiders' collected in Taiwan for study at U-M-Dearborn

Approximately 200 "amazing and very gentle spiders" have taken up residence in a lab in the basement of the Science Building on the U-M-Dearborn campus. They were collected in Taiwan by U-M-Dearborn biology Professor Anne Danielson-Francois and two students who joined her there earlier this summer on a monthlong research expedition.
Anne Danielson-Francois, a biology professor at U-M-Dearborn, is conducting research on the mating behavior of orb-weaving spiders.

The females of the species Nephila pilipes are approximately the size of a human hand. "Because it's a subtropical environment, the insects grow very big and so the spiders grow big, too," Danielson-Francois says. "They're used to eating things as large as my fist."

In the wild the spiders' diets include large beetles and praying mantises. In the Science Building lab, Danielson-Francois and her students are feeding them crickets and flies.

Danielson-Francois is conducting research on the mating behavior of orb-weaving spiders, specifically on "mechanisms of sperm competition" and the evolution of small male body size in spiders.

Nephila pilipes are an extreme example of "sexual-size dimorphism," she says. "The males are tiny, while the females are more than 5 inches across." Their webs are approximately 6 feet in circumference.

The students who joined Danielson-Francois in Taiwan, Nina Cole and Joseph Stude, continue work on the research project at U-M-Dearborn. The research, a collaboration between Professor I-Min Tso of Tunghai University in Taiwan and Danielson-Francois, has been supported by U-M-Dearborn grants, as well as support from Tunghai University and external agencies.