Prove your humanity

Invasive species tend to do well in new places, and they can push out native species. There’s an assumption that they do better in the same kind of environment as the country they came from.

But scientists have found that some invasive plants can change and adapt to new continents and new climates.

Jacob Barney is an associate professor in the College of Agriculture and Life Sciences at Virginia Tech. He and his colleagues examined more than 800 plant species in a new study in the journal Nature Ecology & Evolution.

“There’s been this underlying assumption for hundreds of years that climate influences where species occur,” he says. “What we found was in contradiction to this long-held assumption. In fact, we found that the majority of plant species actually do change once they move to new continents.”

For example, they were asking the question: If a plant occurs in cool, wet places in Europe, is it more likely to occur in cool, wet places in the United States?

“And in fact, we found they are not, they’re in different environments in new locations, and this is a sort of fundamental change in how we view plant species that have been under study since Darwin sailed on the Beagle,” he says.

Barney says not all plant species appear to behave the same way.

“So annual plants actually expand less so than long-lived woody plants. One of the most important things we found is that plant species that humans are cultivating, so the ones we buy at Lowe’s and Home Depot to plant in our gardens, we’re actually perhaps helping them colonize new climates that they wouldn’t otherwise be able to do well in,” he says.

He says this could have implications for how we predict where new invaders might do well, and how we try to control them once they do get established here.

“Because one of the things that we’ve learned over time is that once an invasive plant establishes it’s really difficult to remove. So now, we have a better capability of understanding where they might move in the future so we can prevent that,” he says.