A study illustrates how an unprecedented number of insects are wreaking havoc on plants
Despite decreased bug populations, researchers at the University of Wyoming discovered that insects are nevertheless causing tremendous damage to plants.
The study is the first of its type, comparing insect herbivore damage to modern-era plants with that of preserved leaves dating back to the late Cretaceous period, about 67 million years ago. The University’s research and findings were published in the journal ‘Proceedings of the National Academy of Sciences.’
“Our work bridges the gap between those who study plant-insect interactions in deep time using fossils and those who study such interactions in a modern context using fresh leaf material,” says lead researcher Lauren Azevedo-Schmidt, a UW PhD graduate who is now a postdoctoral research associate at the University of Maine.
“The disparity in insect damage between the present era and the fossilised record is startling,” said Schmidt.
Azevedo-Schmidt collaborated on the study with UW Department of Botany and Department of Geology and Geophysics Professor Ellen Currano and University of California-Davis Assistant Professor Emily Meineke.
The researchers compared fossilised leaves with insect feeding damage from the Late Cretaceous to the Pleistocene epochs, roughly 2 million years ago, to leaves gathered by Azevedo-Schmidt from three current forests. The thorough study examined many types of insect damage, discovering significant increases in all contemporary damage compared to the fossil record.
“Our findings show that, despite widespread insect decreases, plants in the present era are experiencing unprecedented levels of insect damage,” the authors stated, suggesting that the disparity can be explained by human activity.
More research is needed to pinpoint the precise causes of increased insect damage to plants, although scientists believe that a rising climate, urbanisation, and the introduction of invasive species have all played a role.
“We hypothesise that humans have influenced (insect) damage frequencies and diversities within modern woods,” the researchers said. “Consistent with this notion, early 2000s herbarium specimens were 23% more likely to exhibit insect damage than early 1900s specimens, a pattern that has been connected to climate warming.”
However, they argue that climate change does not entirely explain the increase in insect damage.
“This research implies that the extent of human influence on plant-insect interactions is influenced not just by climate change but also by how humans interact with the terrestrial landscape,” the researchers concluded.
(source : ANI)
