Adam Summers, a UC Irvine assistant professor of ecology and evolutionary biology, was among the team of scientists who made the discovery using zebra tarantulas from Costa Rica. The team found that the tarantulas secrete silk from spigots on their legs, allowing them to better cling to surfaces. Until now, spiders were only known to spin silk from spinnerets located on their abdomen and to use the silk to form webs for protection and capturing prey rather than for locomotion.
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“If we find that other spiders in addition to these tarantulas have the ability to secrete silk from their feet, this could represent a major change in our evolutionary hypothesis regarding spider silk,” Summers said. “It could mean that silk production actually originated in the feet to increase traction, with the diversity of spinneret silk evolving later.”
Tarantulas produce silk from their feet (UC Irvine, via Science Blog)