Bed bugs have been silently accompanying humans for over 60,000 years, with their origins tracing back to ancient animal hosts. A new genomic study suggests they transitioned from bats to Neanderthals, marking the beginning of a complex evolutionary relationship with humans.
The insects’ ability to adapt to different environments and host species has allowed them to thrive despite various human activities, such as cave settlement and urbanization. Researchers have found that bed bugs reveal more about their co-evolutionary dynamics than they do about themselves.
A recent study published in Biology Letters suggests that bed bugs likely jumped from bat hosts to Neanderthals around 60,000 years ago, setting the stage for their persistence in human environments. This host transfer may have resulted in reduced genetic diversity in the human-associated lineage.
The research indicates that while both lineages of bed bugs initially declined during the Last Glacial Maximum, only the human-associated lineage rebounded and expanded its population. The scientists compared the complete genome sequence of two distinct bed bug lineages and found a parallel evolution between humans and their parasitic companions.
The establishment of cities like Mesopotamia around 12,000 years ago coincided with the expansion of human bed bug populations. As humans shifted to permanent dwellings, the bugs adapted alongside them, securing more stable hosts and spreading globally through trade and migration.
The widespread use of DDT in the 20th century led to a significant crash in bed bug populations, but they began to reappear and resist pesticides within five years. A related study suggests that pesticide resistance may not result from a single gene mutation, but rather broader genomic responses.
Understanding how human-associated bed bugs evolved—and why bat-associated lineages failed to recover—offers insights into co-evolution and the biological impacts of human behavior on pest dynamics. This unique case study highlights the complex relationships between humans, their environments, and the insects they interact with.
Source: https://indiandefencereview.com/bed-bugs-may-be-the-first-human-pest