Three Silkworm Cocoons Predate the Silk Road by Nearly 2,000 Years

Somebody got to Uzbekistan with silkworms nearly 2,000 years before the Silk Road existed. We're only just finding out.

Three well-preserved cocoons recovered from an archaeological site in Uzbekistan are pushing back the earliest verified date for silkworms cultivated outside China by nearly two millennia, to roughly 4,000 years ago. The Silk Road, the legendary trade network that carried sericulture westward from China, didn't get going until around the second century BCE.

Researchers ran micromorphological and proteomics analyses on the cocoons from the Sapalli Tepe site, dated to roughly 2000 to 1500 BCE, and identified them as Bombyx mori, the domesticated silkworm, directly radiocarbon-dated to between 1940 and 1765 BCE. That's the oldest physical evidence of Bombyx cocoons on record, anywhere.

One of the cocoons appears to have been allowed to hatch, leaving a smooth opening where the moth emerged. That matters because it suggests these early Central Asian silk producers may have been spinning shorter fibers from hatched cocoons rather than preserving one long filament by killing the moth inside, as was more typical in ancient Chinese silk production.

The cocoons didn't travel alone. At the same site, researchers found chunks of charcoal identified as remnants of mulberry trees, the silkworm's obligate food source and a tree not native to Central Asia. The authors point to the mulberry-rich southern slopes of the Himalayas as one possible route west, though other routes remain plausible. Someone wasn't just moving worms. They were moving the whole operation.

The silk was moving long before anyone thought to name the road.

Read the full story at WashU The Source, July 24, 2026

Hot Take: Nice to know people invented international supply chains before they invented catchy names for them.