Oh rats! Did Zheng He’s Ming era Treasure Fleet help spread rodents around the world?

15th century imperial silk paintings hint that explorer’s voyages may have carried some unintended passengers, researchers say

Reading Time:3 minutes

Ancient imperial paintings from the Ming dynasty suggest that brown rats originally found in China may have been stowaways on ships used by explorer Zheng He. Image: Handout

Published: 12:00pm, 18 Apr 2025Updated: 12:09pm, 18 Apr 2025

Ancient silk paintings dating to China’s Ming dynasty have yielded new clues about the domestication of brown rats, which according to researchers, could have spread to the rest of the world while the treasure ship fleets of explorer Zheng He ruled the oceans.

The artwork could be the earliest evidence of such domestication, shedding light on the taming of an animal that is vital to biological and clinical research.

“The imperial paintings, The Silk Scroll of Three Rats, depicted domesticated brown rats with coat colour variation in China during AD1425–1435,” the team wrote in a paper published in the peer-reviewed journal npj Heritage Science on April 12.

One of the rats depicted in the Ming dynasty imperial scrolls. Image: Handout

“It was more than two centuries older than the known record in Japan, presenting the earliest evidence of brown rat domestication.”

The researchers said that based on the inferred pattern of the introduction of wild brown rats across the world, domesticated brown rats may have spread by stowing away on ships used by admiral Zheng He during the Ming dynasty (1368-1644). The expeditions involved tens of thousands of men and hundreds of ships known as the Treasure Fleet.

Brown rats, also known as common or street rats, are a widespread species of rat found around the world, but are believed to have originated in northern China and Mongolia.

The domesticated forms of the brown rat include fancy rats, which are kept as pets, as well as laboratory rats. Laboratory rats are one of the most common animals used in biological research, but tracing the early domestication of these creatures has proven challenging.