Invasive species present an interesting paradox for geneticists. Because their founding populations tend to be small, they have less genetic diversity, which means they have a limited evolutionary toolkit to adapt to their new home. And yet, many of them seem to thrive.
So what gives?
New research into spotted lanternflies, published in the Proceedings of the Royal Society B: Biological Sciences, offers some insights into this ecological conundrum.
Originally from China, spotted lanternflies first came to the United States in 2014. Since then, their populations have skyrocketed, wreaking havoc on native plant life and threatening vineyards. To combat the scourge, states and municipalities have issued “kill-on-sight” orders, urging citizens to squish any invaders.
To find out why they’ve adapted so successfully to their new home, researchers from New York University sequenced the genomes of lanternflies in both rural and urban parts of China as well as the U.S. They found that while the invasive lanternflies in the U.S. were genetically similar in areas as far as 120 miles apart, the urban and rural lanternflies of China showed significant genetic differences despite only being separated by about 20 miles.
Read more: “We Crush, Poison, and Destroy Insects at Our Own Peril”
Taking a closer look at these differences, researchers discovered that urban lanternflies in both countries displayed changes in genes related to stress responses, which could allow them to thrive in bustling cities.
“We think that this may indicate how lanternflies have evolved to survive in hot, polluted, pesticide-heavy cities—and not just in their native China, but in the U.S. as well, which may be helping them spread and creating new potential problems with control in the future,” study author Fallon Meng explained in a statement.
The “invasion force” of lanternflies that established a beachhead in the U.S. likely came from the hardened city-dwelling lanternflies of China, which explains why New York City is besieged by the pests every spring. “Cities can act as evolutionary incubators that may help an invasive species to better deal with pressures like heat and pesticides, which then helps them to better adapt to new environments,” Feng said.
The researchers hope these new findings will lead to a more comprehensive approach to invasive species research that incorporates urbanization trends.
“In our increasingly urban world, we should be studying invasive species and urbanization as interconnected parts of a whole. These two major aspects of global change are too often studied in isolation, but their effects can compound in synergistic and surprising ways, as we are seeing here with the spotted lanternfly,” study co-author Kristin Winchell added.
In the meantime, here’s a pro-tip for lanternfly assassins: They only have three big jumps in them. After that, they become exhausted. Stick with them through the third jump, and you can send them on a one-way trip to squish city. 
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Lead image: Jay Ondreicka / Shutterstock
