Stan Harpole, assistant professor of ecology, evolution and organismal biology at Iowa State University, is founding organizer of a team of more than 70 researchers working at 65 sites worldwide that tested that assumption.
They wanted to know if it is true that problematic invasive species often spread widely in their new habitats because they don’t encounter predators or diseases that help keep them in check in their home ranges.
“There is this assumption that when plants invade a new area that they become much more abundant in the new area than they were in the native areas,” said Harpole. “It turns out that, on average, they aren’t any more abundant away from home than they are at home.”
Harpole says there is a “rule of 10s” that can apply to invasive species.
“Of, say, 100 plants that arrive in a new area, only about 10 percent of those will survive without being in a greenhouse or some other controlled area,” said Harpole. “Of those 10 that can survive, only about 10 percent of those really cause problems.
“When you think about all the species we’ve brought over from other areas, relatively few have become serious pest species. The problem is we’ve brought over so many that quite a few have become major problems and they get a lot of attention.”
Harpole points to the kudzu plant as an example.
Kudzu was introduced from Asia as a soil erosion plant more than a century ago. It now chokes out native species from Texas to Maine to Florida, according to the U.S. Department of Agriculture.
Problem plants like this are uncommon when compared to all the exotic species in a region, but they do get the most interest and may give the impression that species that escape their home range often spread and take over new habitats and become more abundant than before, says Harpole.
Invasion can also be thought of more generally as a process in which new species enter new habitats. Even plants now considered native were once invaders, says Harpole.
When glaciers receded from the Midwest 10,000 years ago, there were no native species in the area – the retreating ice left bare ground open for invasion.
“All the plants that are now seen as native were invasive in the past in the sense that they had to spread across the landscape,” he said.
“What’s different today is that we move plants so much faster than they would move by themselves. Now a species can become global in a matter of years, where it may have taken tens of thousands of years in the past,” said Harpole.
Harpole is coauthor of a research paper led by Jennifer Firn of Queensland University of Technology, Australia, and is published in the journal Ecology Letters. Coordination of the study was funded by the National Science Foundation.
Stanley Harpole, Ecology Evolution and Organismal Biology, 515-294-7253, firstname.lastname@example.org
Stanley Harpole | Newswise Science News
Litter is present throughout the world’s oceans: 1,220 species affected
27.03.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung
International network connects experimental research in European waters
21.03.2017 | Leibniz-Institut für Gewässerökologie und Binnenfischerei (IGB)
The Institute of Semiconductor Technology and the Institute of Physical and Theoretical Chemistry, both members of the Laboratory for Emerging Nanometrology (LENA), at Technische Universität Braunschweig are partners in a new European research project entitled ChipScope, which aims to develop a completely new and extremely small optical microscope capable of observing the interior of living cells in real time. A consortium of 7 partners from 5 countries will tackle this issue with very ambitious objectives during a four-year research program.
To demonstrate the usefulness of this new scientific tool, at the end of the project the developed chip-sized microscope will be used to observe in real-time...
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
30.03.2017 | Health and Medicine
30.03.2017 | Health and Medicine
30.03.2017 | Medical Engineering