BBC SCIENCE FOCUS - Bed bugs have been around longer than humans. When researchers used bed bug DNA to get an idea of when they first evolved, they found that the ancestors of today’s bed bugs were already tiny but successful predators over 115 million years ago, during the reign of the dinosaurs.
What they were preying on back then, we don’t know, possibly ancient birds. What we do know is that when the first bats appeared, bed bugs were present.
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While the common bed bug is the most widespread, the rounder and chubbier tropical bed bugs have recently started showing up all over the northern hemisphere, according to Prof Chow-Yang Lee, chair of urban entomology at University of California, Riverside.