Bed bugs aren’t just a nuisance to humans – they annoy bats too.
Lindsay Miles, postdoctoral researcher at Virginia Tech, looks at the genetics of these pests.
I look through the lens of population genetics and molecular evolution to understand how urbanization impacts organisms. I am co-founder of the urban evolution blog that summarizes urban evolutionary research for the public. I am also part of the Urban Eco-Evo Network, a group of collaborative scientists that are integrating our fields of research to understand the eco-evolutionary dynamics of urbanization. I am currently studying how urbanization and pesticide use can influence genomic evolution in bed bugs.
Bed Bugs
Ever since a few enterprising bed bugs hopped off a bat and attached themselves to a Neanderthal walking out of a cave 60,000 years ago, bed bugs have enjoyed a thriving relationship with their human hosts.
But that was not the case for the unadventurous bed bugs that stayed with the bats — their populations have continued to decline since the last Ice Age.
Here in the Booth Lab, we compared the whole genome sequence of these two genetically distinct lineages of bed bugs. It showed us the human-associated lineage followed a similar demographic pattern as humans, and may well be the first true urban pest.
Working alongside Warren Booth, the Joseph R. and Mary W. Wilson Urban Entomology Associate Professor, we specifically looked at changes in the bugs’ effective population size, which means the number of breeding individuals contributing to the next generation. While the bat-friendly bed bugs’ numbers continue to decline, their human-friendly cousins increased as human populations grew and communities expanded.
What’s exciting about this is that it starts to provide information we can use to better predict the spread of pests and diseases under urban population expansion.
And since the two lineages don’t have enough genetic differences to have evolved into two distinct species, we can really identify and investigate the most recent evolutionary alterations between the two. That will be especially interesting for examining the last 100 to 120 years because once DDT, otherwise known as dichloro-diphenyl-trichloroethane, was introduced for pest control, bed bug populations crashed, but within five years they started reappearing and were resisting the pesticide.
If we can better understand how they survived and began to thrive back then, we hope to better navigate future outbreaks. We really do believe that gaining a better understanding of the bed bugs’ past, will better set up a future of not letting them bite.
