Of the 100 known bedbug species, the majority feed on bats. Only two species feed on humans. Photo by Pavel Krasensky/Shutterstock
May 16 (UPI) -- Bedbugs are notoriously difficult to eradicate. Not even the fiery asteroid impact that wiped out the dinosaurs could rid Earth of its bedbug infestation.
DNA analysis of some 30 different bedbug species showed the insect has been around for at least 115 million years.
Previously, scientists suggested bedbugs emerged between 50 and 60 million years ago. Bats were supposedly the blood-suckers' first victims. But the latest findings -- published this week in the journal Current Biology -- proved the insect predates the bat by some 50 million years.
"To think that the pests that live in our beds today evolved more than 100 million years ago and were walking the earth side by side with dinosaurs, was a revelation," Mike Siva-Jothy, professor of animal and plant sciences at the University of Sheffield, said in a news release. "It shows that the evolutionary history of bed bugs is far more complex than we previously thought."
Initially, researchers wanted to better understand the insect's practice of "traumatic insemination." Males stab their dagger-like penis directly into the bloodstream of females.
Siva-Jothy and his research partners spent 15 years collecting bedbug specimens from remote caves and cliffs. After researchers collected specimens from dozens of species, they realized they could track the insect's genetic origins.
In addition to the timing of the insect's origins, the new analysis revealed the complexity of different bedbug lineages. Some lineages evolved to feed on a single host, while other lineages remain generalists.
Scientists also determined a new species figures out how to start feeding on humans every half a million years. However, the species found most frequently in the beds of humans, the common and the tropical bedbug, predate the emergence of humans by several millions years.
Now that humans are more abundant than ever, however, it is likely a new species will take to the taste of human blood more frequently moving forward.
"These findings will help us better understand how bedbugs evolved the traits that make them effective pests -- that will also help us find new ways of controlling them," Siva-Jothy said.