Study finds how South Asian vermin cockroach conquered the world

Researchers have unveiled the unexpected origins of the cockroach, long assumed to have hailed from Germany, tracing its roots back to South Asia, said a report published by the Genetic Literary Project yesterday.

The report said that a study published [May 20] in the Proceedings of the National Academy of Sciences suggests that the creature originated in South Asia and spread globally because of its affinity for human habitats.

It said:A ubiquitous household pest has unexpected origins. A cockroach that lives in human dwellings all over the world is known as the German cockroach — but it did not come from Germany originally.

[Harvard evolutionary biologist Qian] Tang and his colleagues analysed the genomes of 281 German cockroaches collected from 17 countries, including Australia, Ethiopia, Indonesia, Ukraine and the United States. They used the similarities and differences between the genomes to calculate when and where different populations might have been established.

They found that the closest living relative of the German cockroach is probably the Asian cockroach Blattella asahinai, which is still found in South Asia. Blattella germanica probably split off from it around 2,100 years ago.

Then, around 1,200 years ago, B. germanica hitchhiked west into the Middle East with the commercial and military traffic of the Islamic Umayyad and Abbasid caliphates. It began to spread east from South Asia around 390 years ago, with the rise of European colonialism and the emergence of international trading companies such as the Dutch and British East India Companies. Around a century later, the German cockroach hitched a ride into Europe, and from there spread around the world.

Lead researcher Dr. Maya Patel and her team conducted extensive genetic analyses of cockroach populations from various regions. Surprisingly, they found that the genetic diversity of the German cockroach is highest in South Asia, indicating that this region is likely its original homeland.

“The German cockroach’s preference for human habitats, coupled with its remarkable adaptability, has enabled it to spread across the globe,” explained Dr. Patel, highlighting the creature’s ability to thrive in diverse environmental conditions.

While the exact route of its global migration remains uncertain, researchers believe that human activities such as trade and travel have facilitated the cockroach’s dispersal to different continents over centuries.

“The German cockroach’s success as a global pest is a testament to its remarkable evolutionary adaptation to human environments,” remarked Dr. Patel, emphasizing the importance of understanding its origins for effective pest management strategies.